Abstract

Europium doped zinc thiogallate, ZnGa2S4:Eu2+, has been reported as a saturated green emitting phosphor, suitable as conversion phosphor in white LEDs for lighting or displays. Up to now, no direct proof for the incorporation of Eu2+ in ZnGa2S4 has been given. We combined X-ray diffraction (XRD), cathodoluminescence in electron microscopy (SEM-CL) and X-ray absorption spectroscopy (XAS) to study the incorporation of the europium ions in the host material. The previously reported green luminescence was found to originate from small amounts of unintentionally formed EuGa2S4, and not from europium ions incorporated into ZnGa2S4. EuGa2S4 has a low quantum efficiency (< 20%) and shows strong thermal quenching, already below room temperature. The XAS data analysis suggests that a certain amount of europium might occupy octahedral voids inside the zinc thiogallate lattice in a divalent state. The zinc ion next to these interstitial dopants is then removed for charge compensation. Notwithstanding the possible, but limited, incorporation of Eu2+ in ZnGa2S4, these ions do not activate any luminescence as was shown with SEM-CL.

© 2013 OSA

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. V. Bachmann, C. Ronda, and A. Meijerink, “Temperature quenching of yellow Ce3+ luminescence in YAG:Ce,” Chem. Mater.21(10), 2077–2084 (2009).
    [CrossRef]
  2. R. Mueller-Mach, G. Mueller, M. R. Krames, H. A. Hoppe, F. Stadler, W. Schnick, T. Juestel, and P. Schmidt, “Highly efficient all-nitride phosphor-converted white light emitting diode,” Physica Status Solidi a-Applications and Materials Science202(9), 1727–1732 (2005).
    [CrossRef]
  3. I. H. Cho, G. Anoop, D. W. Suh, S. J. Lee, and J. S. Yoo, “On the stability and reliability of Sr1-xBaxSi2O2N2:Eu2+ phosphors for white LED applications,” Opt. Mater. Express2(9), 1292–1305 (2012).
    [CrossRef]
  4. R. J. Xie, N. Hirosaki, and T. Takeda, “Wide color gamut backlight for liquid crystal displays using three-band phosphor-converted white light-emitting diodes,” Appl. Phys. Express2, 022401 (2009).
    [CrossRef]
  5. M. H. Crawford, “LEDs for solid-state lighting: performance challenges and recent advances,” IEEE J. Sel. Top. Quant.15(4), 1028–1040 (2009).
    [CrossRef]
  6. J. H. Oh, S. J. Yang, Y. G. Sung, and Y. R. Do, “Excellent color rendering indexes of multi-package white LEDs,” Opt. Express20(18), 20276–20285 (2012).
    [CrossRef] [PubMed]
  7. J. H. Oh, S. J. Yang, Y. G. Sung, and Y. R. Do, “Improved color coordinates of green monochromatic pc-LED capped with a band-pass filter,” Opt. Express21(4), 4539–4550 (2013).
    [CrossRef] [PubMed]
  8. P. F. Smet, A. B. Parmentier, and D. Poelman, “Selecting conversion phosphors for white light-emitting diodes,” J. Electrochem. Soc.158(6), R37–R54 (2011).
    [CrossRef]
  9. T. L. Barry, “Fluorescence of Eu2+-activated phases in binary alkaline earth orthosilicate systems,” J. Electrochem. Soc.115(11), 1181–1184 (1968).
    [CrossRef]
  10. Y. Shimomura, T. Honma, M. Shigeiwa, T. Akai, K. Okamoto, and N. Kijima, “Photoluminescence and crystal structure of green-emitting Ca3Sc2Si3O12:Ce3+ phosphor for white light emitting diodes,” J. Electrochem. Soc.154(1), J35–J38 (2007).
    [CrossRef]
  11. J. J. Joos, K. W. Meert, A. B. Parmentier, D. Poelman, and P. F. Smet, “Thermal quenching and luminescence lifetime of saturated green Sr1-xEuxGa2S4 phosphors,” Opt. Mater.34(11), 1902–1907 (2012).
    [CrossRef]
  12. S. Iida, A. Kato, M. Tanaka, H. Najafov, and H. Ikuno, “Photoluminescence characterization of rare-earth stoichiometric compounds of EuGa2S4,” J. Phys. Chem. Solids64(9-10), 1815–1819 (2003).
    [CrossRef]
  13. R. J. Yu, H. K. Yang, B. K. Moon, B. C. Choi, and J. H. Jeong, “Luminescence properties of stoichiometric EuM2S4 (M = Ga, Al) conversion phosphors for white LED applications,” Physica Status Solidi a-Applications and Materials Science209(12), 2620–2625 (2012).
    [CrossRef]
  14. C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
    [CrossRef] [PubMed]
  15. V. Bachmann, T. Justel, A. Meijerink, C. Ronda, and P. J. Schmidt, “Luminescence properties of SrSi2O2N2 doped with divalent rare earth ions,” J. Lumin.121(2), 441–449 (2006).
    [CrossRef]
  16. R. J. Xie, N. Hirosaki, Y. Q. Li, and T. Takeda, “Rare-earth activated nitride phosphors: synthesis, luminescence and applications,” Materials3(6), 3777–3793 (2010).
    [CrossRef]
  17. M. Seibald, T. Rosenthal, O. Oeckler, C. Maak, A. Tücks, P. J. Schmidt, D. Wiechert, and W. Schnick, “New polymorph of the highly efficient LED-phosphor SrSi2O2N2:Eu2+ – polytypism of a layered oxonitridosilicate,” Chem. Mater.25(9), 1852–1857 (2013).
    [CrossRef]
  18. R. J. Xie, N. Hirosaki, H. L. Li, Y. Q. Li, and M. Mitomo, “Synthesis and photoluminescence properties of beta-sialon: Eu2+ (Si6-zAlzOzN8-z:Eu2+),” J. Electrochem. Soc.154, J314–J319 (2007).
    [CrossRef]
  19. Y. C. Chiu, C. H. Huang, T. J. Lee, W. R. Liu, Y. T. Yeh, S. M. Jang, and R. S. Liu, “Eu2+-activated silicon-oxynitride Ca3Si2O4N2: a green-emitting phosphor for white LEDs,” Opt. Express19(S3Suppl 3), A331–A339 (2011).
    [CrossRef] [PubMed]
  20. Y. Q. Li, C. M. Fang, G. de With, and H. T. Hintzen, “Preparation, structure and photoluminescence properties of Eu2+ and Ce3+-doped SrYSi4N7,” J. Solid State Chem.177(12), 4687–4694 (2004).
    [CrossRef]
  21. M. M. Yuta and W. B. White, “Photoluminescence of sulfide phosphors with the MB2S4 composition,” J. Electrochem. Soc.139(8), 2347–2352 (1992).
    [CrossRef]
  22. J. W. Kim and Y. J. Kim, “Synthesis and luminescent characterization of zinc thiogallate,” J. Eur. Ceram. Soc.27(13-15), 3667–3670 (2007).
    [CrossRef]
  23. Y. K. Kim, D. H. Cho, Y. K. Jeong, M. K. Nah, K. B. Kim, and J. G. Kang, “Luminescence characterization of (Ca1-xZnx)Ga2S4:Eu2+ phosphors for a white light-emitting diode,” Mater. Res. Bull.45(8), 905–909 (2010).
    [CrossRef]
  24. R. Yu, R. X. Luan, C. F. Wang, J. T. Chen, Z. X. Wang, B. K. Moon, and J. H. Jeong, “Photoluminescence properties of green emitting ZnGa2S4:Eu2+ phosphor,” J. Electrochem. Soc.159(5), J188–J192 (2012).
    [CrossRef]
  25. Y. K. Jeong, D. H. Cho, K. B. Kim, and J. G. Kang, “Highly luminescent (Zn0.6Sr0.3Mg0.1)2Ga2S5:Eu2+ green phosphors for a white light-emitting diode,” Bull. Korean Chem. Soc.33(8), 2523–2528 (2012).
    [CrossRef]
  26. J. W. Kim and Y. J. Kim, “Optical properties of eu doped M-Ga2S4 (M: Zn, Ca, Sr) phosphors for white light emitting diodes,” J. Nanosci. Nanotechnol.7(11), 4065–4068 (2007).
    [CrossRef] [PubMed]
  27. B. G. Tagiev, G. G. Guseinov, R. B. Dzhabbarov, O. B. Tagiev, N. N. Musaeva, and A. N. Georgobiani, “Synthesis and luminescent properties of ZnGa2S4:Eu,F and ZnGa2O4:Eu,F,” Inorg. Mater.36(12), 1189–1191 (2000).
    [CrossRef]
  28. C. Wickleder, S. Zhang, and H. Haeuseler, “Photoluminescence of ZnGa2S4:Eu2+,” Z. Kristallogr.220(2-3-2005), 277–280 (2005).
    [CrossRef]
  29. H. A. Höppe, “Recent developments in the field of inorganic phosphors,” Angew. Chem. Int. Ed. Engl.48(20), 3572–3582 (2009).
    [CrossRef] [PubMed]
  30. G. Derbyshire, K. C. Cheung, P. Sangsingkeow, and S. S. Hasnain, “A low-profile monolithic multi-element Ge detector for X-ray fluorescence applications,” J. Synchrotron Radiat.6(2), 62–63 (1999).
    [CrossRef]
  31. B. Ravel and M. Newville, “ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT,” J. Synchrotron Radiat.12(4), 537–541 (2005).
    [CrossRef] [PubMed]
  32. S. H. M. Poort, A. Meyerink, and G. Blasse, “Lifetime measurements in Eu2+-doped host lattices,” J. Phys. Chem. Solids58(9), 1451–1456 (1997).
    [CrossRef]
  33. R. B. Jabbarov, C. Chartier, B. G. Tagiev, O. B. Tagiev, N. N. Musayeva, C. Barthou, and P. Benalloul, “Radiative properties of Eu2+ in BaGa2S4,” J. Phys. Chem. Solids66(6), 1049–1056 (2005).
    [CrossRef]
  34. P. F. Smet, J. E. Van Haecke, R. L. Van Meirhaeghe, and D. Poelman, “Crystallographic and luminescent properties of orthorhombic BaAl2S4:Eu powder and thin films,” J. Appl. Phys.98(4), 043512 (2005).
    [CrossRef]
  35. K. T. Lethi, A. Garcia, F. Guillen, and C. Fouassier, “Investigation of the MS-Al2S3 systems (M = Ca, Sr, Ba) and luminescence properties of europium-doped thioaluminates,” Mat. Sci. Eng. B-Solid14, 393–397 (1992).
    [CrossRef]
  36. J. E. Van Haecke, P. F. Smet, and D. Poelman, “Luminescent characterization of CaAl2S4:Eu powder,” J. Lumin.126(2), 508–514 (2007).
    [CrossRef]
  37. P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
    [CrossRef]
  38. V. Bachmann, C. Ronda, O. Oeckler, W. Schnick, and A. Meijerink, “Color point tuning for (Sr,Ca,Ba)Si2O2N2:Eu2+ for white light LEDs,” Chem. Mater.21(2), 316–325 (2009).
    [CrossRef]
  39. B. Henderson and G. F. Imbusch, Optical Spectroscopy of Inorganic Solids (Oxford University Press, Incorporated, 2006).
  40. A. B. Parmentier, P. F. Smet, F. Bertram, J. Christen, and D. Poelman, “Structure and luminescence of (Ca,Sr)2SiS4:Eu2+ phosphors,” J. Phys. D Appl. Phys.43(8), 085401 (2010).
    [CrossRef]
  41. R. D. Shannon, “Revised effective ionic-radii and systematic studies of interatomic distances in halides and chalcogenides,” Acta Crystallogr. A32(5), 751–767 (1976).
    [CrossRef]
  42. P. Dorenbos, “Thermal quenching of Eu2+ 5d-4f luminescence in inorganic compounds,” J. Phys.- Condens. Mat.17(50), 8103–8111 (2005).
    [CrossRef]
  43. P. Dorenbos, “Energy of the first 4f7-> 4f65d transition of Eu2+ in inorganic compounds,” J. Lumin.104(4), 239–260 (2003).
    [CrossRef]
  44. B. G. Yacobi and D. B. Holt, “Cathodoluminescence scanning electron-microscopy of semiconductors,” J. Appl. Phys.59(4), R1–R24 (1986).
    [CrossRef]
  45. C. K. Lowe-Ma and T. A. Vanderah, “Structure of ZnGa2S4, a defect sphalerite derivative,” Acta Crystallogr. C47(5), 919–924 (1991).
    [CrossRef]
  46. A. Eifler, G. Krauss, V. Riede, V. Kramer, and W. Grill, “Optical phonon modes and structure of ZnGa2Se4 and ZnGa2S4,” J. Phys. Chem. Solids66(11), 2052–2057 (2005).
    [CrossRef]
  47. R. Roques, R. Rimet, J. P. Declercq, and G. Germain, “Determination of crystal-structure of EuGa2S4,” Acta Crystallogr. B35(3), 555–557 (1979).
    [CrossRef]
  48. V. K. Pecharsky and P. Y. Zavalij, Fundamentals of Powder Diffraction and Structural Characterization of Materials (Springer, 2005).
  49. N. Avci, K. Korthout, M. A. Newton, P. F. Smet, and D. Poelman, “Valence states of europium in CaAl2O4:Eu phosphors,” Opt. Mater. Express2(3), 321–330 (2012).
    [CrossRef]
  50. K. Korthout, A. B. Parmentier, P. F. Smet, and D. Poelman, “A XAS study of the luminescent Eu centers in thiosilicate phosphors,” Phys. Chem. Chem. Phys.15(22), 8678–8683 (2013).
    [CrossRef] [PubMed]
  51. T. Kobayashi, K. Susa, and S. Taniguchi, “Preparation and semiconductive properties of rock salt type solid-solution systems, Cd1-xMxS (M=Sr, Ca, Mg, Pb, Sn),” J. Phys. Chem. Solids40(10), 781–785 (1979).
    [CrossRef]

2013 (3)

J. H. Oh, S. J. Yang, Y. G. Sung, and Y. R. Do, “Improved color coordinates of green monochromatic pc-LED capped with a band-pass filter,” Opt. Express21(4), 4539–4550 (2013).
[CrossRef] [PubMed]

M. Seibald, T. Rosenthal, O. Oeckler, C. Maak, A. Tücks, P. J. Schmidt, D. Wiechert, and W. Schnick, “New polymorph of the highly efficient LED-phosphor SrSi2O2N2:Eu2+ – polytypism of a layered oxonitridosilicate,” Chem. Mater.25(9), 1852–1857 (2013).
[CrossRef]

K. Korthout, A. B. Parmentier, P. F. Smet, and D. Poelman, “A XAS study of the luminescent Eu centers in thiosilicate phosphors,” Phys. Chem. Chem. Phys.15(22), 8678–8683 (2013).
[CrossRef] [PubMed]

2012 (7)

N. Avci, K. Korthout, M. A. Newton, P. F. Smet, and D. Poelman, “Valence states of europium in CaAl2O4:Eu phosphors,” Opt. Mater. Express2(3), 321–330 (2012).
[CrossRef]

J. J. Joos, K. W. Meert, A. B. Parmentier, D. Poelman, and P. F. Smet, “Thermal quenching and luminescence lifetime of saturated green Sr1-xEuxGa2S4 phosphors,” Opt. Mater.34(11), 1902–1907 (2012).
[CrossRef]

R. J. Yu, H. K. Yang, B. K. Moon, B. C. Choi, and J. H. Jeong, “Luminescence properties of stoichiometric EuM2S4 (M = Ga, Al) conversion phosphors for white LED applications,” Physica Status Solidi a-Applications and Materials Science209(12), 2620–2625 (2012).
[CrossRef]

J. H. Oh, S. J. Yang, Y. G. Sung, and Y. R. Do, “Excellent color rendering indexes of multi-package white LEDs,” Opt. Express20(18), 20276–20285 (2012).
[CrossRef] [PubMed]

I. H. Cho, G. Anoop, D. W. Suh, S. J. Lee, and J. S. Yoo, “On the stability and reliability of Sr1-xBaxSi2O2N2:Eu2+ phosphors for white LED applications,” Opt. Mater. Express2(9), 1292–1305 (2012).
[CrossRef]

R. Yu, R. X. Luan, C. F. Wang, J. T. Chen, Z. X. Wang, B. K. Moon, and J. H. Jeong, “Photoluminescence properties of green emitting ZnGa2S4:Eu2+ phosphor,” J. Electrochem. Soc.159(5), J188–J192 (2012).
[CrossRef]

Y. K. Jeong, D. H. Cho, K. B. Kim, and J. G. Kang, “Highly luminescent (Zn0.6Sr0.3Mg0.1)2Ga2S5:Eu2+ green phosphors for a white light-emitting diode,” Bull. Korean Chem. Soc.33(8), 2523–2528 (2012).
[CrossRef]

2011 (2)

2010 (4)

C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
[CrossRef] [PubMed]

R. J. Xie, N. Hirosaki, Y. Q. Li, and T. Takeda, “Rare-earth activated nitride phosphors: synthesis, luminescence and applications,” Materials3(6), 3777–3793 (2010).
[CrossRef]

Y. K. Kim, D. H. Cho, Y. K. Jeong, M. K. Nah, K. B. Kim, and J. G. Kang, “Luminescence characterization of (Ca1-xZnx)Ga2S4:Eu2+ phosphors for a white light-emitting diode,” Mater. Res. Bull.45(8), 905–909 (2010).
[CrossRef]

A. B. Parmentier, P. F. Smet, F. Bertram, J. Christen, and D. Poelman, “Structure and luminescence of (Ca,Sr)2SiS4:Eu2+ phosphors,” J. Phys. D Appl. Phys.43(8), 085401 (2010).
[CrossRef]

2009 (5)

V. Bachmann, C. Ronda, O. Oeckler, W. Schnick, and A. Meijerink, “Color point tuning for (Sr,Ca,Ba)Si2O2N2:Eu2+ for white light LEDs,” Chem. Mater.21(2), 316–325 (2009).
[CrossRef]

H. A. Höppe, “Recent developments in the field of inorganic phosphors,” Angew. Chem. Int. Ed. Engl.48(20), 3572–3582 (2009).
[CrossRef] [PubMed]

R. J. Xie, N. Hirosaki, and T. Takeda, “Wide color gamut backlight for liquid crystal displays using three-band phosphor-converted white light-emitting diodes,” Appl. Phys. Express2, 022401 (2009).
[CrossRef]

M. H. Crawford, “LEDs for solid-state lighting: performance challenges and recent advances,” IEEE J. Sel. Top. Quant.15(4), 1028–1040 (2009).
[CrossRef]

V. Bachmann, C. Ronda, and A. Meijerink, “Temperature quenching of yellow Ce3+ luminescence in YAG:Ce,” Chem. Mater.21(10), 2077–2084 (2009).
[CrossRef]

2007 (5)

Y. Shimomura, T. Honma, M. Shigeiwa, T. Akai, K. Okamoto, and N. Kijima, “Photoluminescence and crystal structure of green-emitting Ca3Sc2Si3O12:Ce3+ phosphor for white light emitting diodes,” J. Electrochem. Soc.154(1), J35–J38 (2007).
[CrossRef]

R. J. Xie, N. Hirosaki, H. L. Li, Y. Q. Li, and M. Mitomo, “Synthesis and photoluminescence properties of beta-sialon: Eu2+ (Si6-zAlzOzN8-z:Eu2+),” J. Electrochem. Soc.154, J314–J319 (2007).
[CrossRef]

J. E. Van Haecke, P. F. Smet, and D. Poelman, “Luminescent characterization of CaAl2S4:Eu powder,” J. Lumin.126(2), 508–514 (2007).
[CrossRef]

J. W. Kim and Y. J. Kim, “Synthesis and luminescent characterization of zinc thiogallate,” J. Eur. Ceram. Soc.27(13-15), 3667–3670 (2007).
[CrossRef]

J. W. Kim and Y. J. Kim, “Optical properties of eu doped M-Ga2S4 (M: Zn, Ca, Sr) phosphors for white light emitting diodes,” J. Nanosci. Nanotechnol.7(11), 4065–4068 (2007).
[CrossRef] [PubMed]

2006 (1)

V. Bachmann, T. Justel, A. Meijerink, C. Ronda, and P. J. Schmidt, “Luminescence properties of SrSi2O2N2 doped with divalent rare earth ions,” J. Lumin.121(2), 441–449 (2006).
[CrossRef]

2005 (7)

R. Mueller-Mach, G. Mueller, M. R. Krames, H. A. Hoppe, F. Stadler, W. Schnick, T. Juestel, and P. Schmidt, “Highly efficient all-nitride phosphor-converted white light emitting diode,” Physica Status Solidi a-Applications and Materials Science202(9), 1727–1732 (2005).
[CrossRef]

C. Wickleder, S. Zhang, and H. Haeuseler, “Photoluminescence of ZnGa2S4:Eu2+,” Z. Kristallogr.220(2-3-2005), 277–280 (2005).
[CrossRef]

R. B. Jabbarov, C. Chartier, B. G. Tagiev, O. B. Tagiev, N. N. Musayeva, C. Barthou, and P. Benalloul, “Radiative properties of Eu2+ in BaGa2S4,” J. Phys. Chem. Solids66(6), 1049–1056 (2005).
[CrossRef]

P. F. Smet, J. E. Van Haecke, R. L. Van Meirhaeghe, and D. Poelman, “Crystallographic and luminescent properties of orthorhombic BaAl2S4:Eu powder and thin films,” J. Appl. Phys.98(4), 043512 (2005).
[CrossRef]

B. Ravel and M. Newville, “ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT,” J. Synchrotron Radiat.12(4), 537–541 (2005).
[CrossRef] [PubMed]

A. Eifler, G. Krauss, V. Riede, V. Kramer, and W. Grill, “Optical phonon modes and structure of ZnGa2Se4 and ZnGa2S4,” J. Phys. Chem. Solids66(11), 2052–2057 (2005).
[CrossRef]

P. Dorenbos, “Thermal quenching of Eu2+ 5d-4f luminescence in inorganic compounds,” J. Phys.- Condens. Mat.17(50), 8103–8111 (2005).
[CrossRef]

2004 (1)

Y. Q. Li, C. M. Fang, G. de With, and H. T. Hintzen, “Preparation, structure and photoluminescence properties of Eu2+ and Ce3+-doped SrYSi4N7,” J. Solid State Chem.177(12), 4687–4694 (2004).
[CrossRef]

2003 (3)

S. Iida, A. Kato, M. Tanaka, H. Najafov, and H. Ikuno, “Photoluminescence characterization of rare-earth stoichiometric compounds of EuGa2S4,” J. Phys. Chem. Solids64(9-10), 1815–1819 (2003).
[CrossRef]

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

P. Dorenbos, “Energy of the first 4f7-> 4f65d transition of Eu2+ in inorganic compounds,” J. Lumin.104(4), 239–260 (2003).
[CrossRef]

2000 (1)

B. G. Tagiev, G. G. Guseinov, R. B. Dzhabbarov, O. B. Tagiev, N. N. Musaeva, and A. N. Georgobiani, “Synthesis and luminescent properties of ZnGa2S4:Eu,F and ZnGa2O4:Eu,F,” Inorg. Mater.36(12), 1189–1191 (2000).
[CrossRef]

1999 (1)

G. Derbyshire, K. C. Cheung, P. Sangsingkeow, and S. S. Hasnain, “A low-profile monolithic multi-element Ge detector for X-ray fluorescence applications,” J. Synchrotron Radiat.6(2), 62–63 (1999).
[CrossRef]

1997 (1)

S. H. M. Poort, A. Meyerink, and G. Blasse, “Lifetime measurements in Eu2+-doped host lattices,” J. Phys. Chem. Solids58(9), 1451–1456 (1997).
[CrossRef]

1992 (2)

K. T. Lethi, A. Garcia, F. Guillen, and C. Fouassier, “Investigation of the MS-Al2S3 systems (M = Ca, Sr, Ba) and luminescence properties of europium-doped thioaluminates,” Mat. Sci. Eng. B-Solid14, 393–397 (1992).
[CrossRef]

M. M. Yuta and W. B. White, “Photoluminescence of sulfide phosphors with the MB2S4 composition,” J. Electrochem. Soc.139(8), 2347–2352 (1992).
[CrossRef]

1991 (1)

C. K. Lowe-Ma and T. A. Vanderah, “Structure of ZnGa2S4, a defect sphalerite derivative,” Acta Crystallogr. C47(5), 919–924 (1991).
[CrossRef]

1986 (1)

B. G. Yacobi and D. B. Holt, “Cathodoluminescence scanning electron-microscopy of semiconductors,” J. Appl. Phys.59(4), R1–R24 (1986).
[CrossRef]

1979 (2)

R. Roques, R. Rimet, J. P. Declercq, and G. Germain, “Determination of crystal-structure of EuGa2S4,” Acta Crystallogr. B35(3), 555–557 (1979).
[CrossRef]

T. Kobayashi, K. Susa, and S. Taniguchi, “Preparation and semiconductive properties of rock salt type solid-solution systems, Cd1-xMxS (M=Sr, Ca, Mg, Pb, Sn),” J. Phys. Chem. Solids40(10), 781–785 (1979).
[CrossRef]

1976 (1)

R. D. Shannon, “Revised effective ionic-radii and systematic studies of interatomic distances in halides and chalcogenides,” Acta Crystallogr. A32(5), 751–767 (1976).
[CrossRef]

1968 (1)

T. L. Barry, “Fluorescence of Eu2+-activated phases in binary alkaline earth orthosilicate systems,” J. Electrochem. Soc.115(11), 1181–1184 (1968).
[CrossRef]

Akai, T.

Y. Shimomura, T. Honma, M. Shigeiwa, T. Akai, K. Okamoto, and N. Kijima, “Photoluminescence and crystal structure of green-emitting Ca3Sc2Si3O12:Ce3+ phosphor for white light emitting diodes,” J. Electrochem. Soc.154(1), J35–J38 (2007).
[CrossRef]

Anoop, G.

Avci, N.

Bachmann, V.

V. Bachmann, C. Ronda, O. Oeckler, W. Schnick, and A. Meijerink, “Color point tuning for (Sr,Ca,Ba)Si2O2N2:Eu2+ for white light LEDs,” Chem. Mater.21(2), 316–325 (2009).
[CrossRef]

V. Bachmann, C. Ronda, and A. Meijerink, “Temperature quenching of yellow Ce3+ luminescence in YAG:Ce,” Chem. Mater.21(10), 2077–2084 (2009).
[CrossRef]

V. Bachmann, T. Justel, A. Meijerink, C. Ronda, and P. J. Schmidt, “Luminescence properties of SrSi2O2N2 doped with divalent rare earth ions,” J. Lumin.121(2), 441–449 (2006).
[CrossRef]

Barry, T. L.

T. L. Barry, “Fluorescence of Eu2+-activated phases in binary alkaline earth orthosilicate systems,” J. Electrochem. Soc.115(11), 1181–1184 (1968).
[CrossRef]

Barthou, C.

R. B. Jabbarov, C. Chartier, B. G. Tagiev, O. B. Tagiev, N. N. Musayeva, C. Barthou, and P. Benalloul, “Radiative properties of Eu2+ in BaGa2S4,” J. Phys. Chem. Solids66(6), 1049–1056 (2005).
[CrossRef]

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

Benalloul, P.

R. B. Jabbarov, C. Chartier, B. G. Tagiev, O. B. Tagiev, N. N. Musayeva, C. Barthou, and P. Benalloul, “Radiative properties of Eu2+ in BaGa2S4,” J. Phys. Chem. Solids66(6), 1049–1056 (2005).
[CrossRef]

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

Bertram, F.

A. B. Parmentier, P. F. Smet, F. Bertram, J. Christen, and D. Poelman, “Structure and luminescence of (Ca,Sr)2SiS4:Eu2+ phosphors,” J. Phys. D Appl. Phys.43(8), 085401 (2010).
[CrossRef]

Blasse, G.

S. H. M. Poort, A. Meyerink, and G. Blasse, “Lifetime measurements in Eu2+-doped host lattices,” J. Phys. Chem. Solids58(9), 1451–1456 (1997).
[CrossRef]

Börger, S. L.

C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
[CrossRef] [PubMed]

Boyko, T. D.

C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
[CrossRef] [PubMed]

Braun, C.

C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
[CrossRef] [PubMed]

Chartier, C.

R. B. Jabbarov, C. Chartier, B. G. Tagiev, O. B. Tagiev, N. N. Musayeva, C. Barthou, and P. Benalloul, “Radiative properties of Eu2+ in BaGa2S4,” J. Phys. Chem. Solids66(6), 1049–1056 (2005).
[CrossRef]

Chen, J. T.

R. Yu, R. X. Luan, C. F. Wang, J. T. Chen, Z. X. Wang, B. K. Moon, and J. H. Jeong, “Photoluminescence properties of green emitting ZnGa2S4:Eu2+ phosphor,” J. Electrochem. Soc.159(5), J188–J192 (2012).
[CrossRef]

Cheung, K. C.

G. Derbyshire, K. C. Cheung, P. Sangsingkeow, and S. S. Hasnain, “A low-profile monolithic multi-element Ge detector for X-ray fluorescence applications,” J. Synchrotron Radiat.6(2), 62–63 (1999).
[CrossRef]

Chiu, Y. C.

Cho, D. H.

Y. K. Jeong, D. H. Cho, K. B. Kim, and J. G. Kang, “Highly luminescent (Zn0.6Sr0.3Mg0.1)2Ga2S5:Eu2+ green phosphors for a white light-emitting diode,” Bull. Korean Chem. Soc.33(8), 2523–2528 (2012).
[CrossRef]

Y. K. Kim, D. H. Cho, Y. K. Jeong, M. K. Nah, K. B. Kim, and J. G. Kang, “Luminescence characterization of (Ca1-xZnx)Ga2S4:Eu2+ phosphors for a white light-emitting diode,” Mater. Res. Bull.45(8), 905–909 (2010).
[CrossRef]

Cho, I. H.

Choi, B. C.

R. J. Yu, H. K. Yang, B. K. Moon, B. C. Choi, and J. H. Jeong, “Luminescence properties of stoichiometric EuM2S4 (M = Ga, Al) conversion phosphors for white LED applications,” Physica Status Solidi a-Applications and Materials Science209(12), 2620–2625 (2012).
[CrossRef]

Christen, J.

A. B. Parmentier, P. F. Smet, F. Bertram, J. Christen, and D. Poelman, “Structure and luminescence of (Ca,Sr)2SiS4:Eu2+ phosphors,” J. Phys. D Appl. Phys.43(8), 085401 (2010).
[CrossRef]

Crawford, M. H.

M. H. Crawford, “LEDs for solid-state lighting: performance challenges and recent advances,” IEEE J. Sel. Top. Quant.15(4), 1028–1040 (2009).
[CrossRef]

de With, G.

Y. Q. Li, C. M. Fang, G. de With, and H. T. Hintzen, “Preparation, structure and photoluminescence properties of Eu2+ and Ce3+-doped SrYSi4N7,” J. Solid State Chem.177(12), 4687–4694 (2004).
[CrossRef]

Declercq, J. P.

R. Roques, R. Rimet, J. P. Declercq, and G. Germain, “Determination of crystal-structure of EuGa2S4,” Acta Crystallogr. B35(3), 555–557 (1979).
[CrossRef]

Derbyshire, G.

G. Derbyshire, K. C. Cheung, P. Sangsingkeow, and S. S. Hasnain, “A low-profile monolithic multi-element Ge detector for X-ray fluorescence applications,” J. Synchrotron Radiat.6(2), 62–63 (1999).
[CrossRef]

Do, Y. R.

Dorenbos, P.

P. Dorenbos, “Thermal quenching of Eu2+ 5d-4f luminescence in inorganic compounds,” J. Phys.- Condens. Mat.17(50), 8103–8111 (2005).
[CrossRef]

P. Dorenbos, “Energy of the first 4f7-> 4f65d transition of Eu2+ in inorganic compounds,” J. Lumin.104(4), 239–260 (2003).
[CrossRef]

Dzhabbarov, R. B.

B. G. Tagiev, G. G. Guseinov, R. B. Dzhabbarov, O. B. Tagiev, N. N. Musaeva, and A. N. Georgobiani, “Synthesis and luminescent properties of ZnGa2S4:Eu,F and ZnGa2O4:Eu,F,” Inorg. Mater.36(12), 1189–1191 (2000).
[CrossRef]

Eifler, A.

A. Eifler, G. Krauss, V. Riede, V. Kramer, and W. Grill, “Optical phonon modes and structure of ZnGa2Se4 and ZnGa2S4,” J. Phys. Chem. Solids66(11), 2052–2057 (2005).
[CrossRef]

Emirov, Y. N.

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

Fang, C. M.

Y. Q. Li, C. M. Fang, G. de With, and H. T. Hintzen, “Preparation, structure and photoluminescence properties of Eu2+ and Ce3+-doped SrYSi4N7,” J. Solid State Chem.177(12), 4687–4694 (2004).
[CrossRef]

Fouassier, C.

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

K. T. Lethi, A. Garcia, F. Guillen, and C. Fouassier, “Investigation of the MS-Al2S3 systems (M = Ca, Sr, Ba) and luminescence properties of europium-doped thioaluminates,” Mat. Sci. Eng. B-Solid14, 393–397 (1992).
[CrossRef]

Garcia, A.

K. T. Lethi, A. Garcia, F. Guillen, and C. Fouassier, “Investigation of the MS-Al2S3 systems (M = Ca, Sr, Ba) and luminescence properties of europium-doped thioaluminates,” Mat. Sci. Eng. B-Solid14, 393–397 (1992).
[CrossRef]

Georgobiani, A. N.

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

B. G. Tagiev, G. G. Guseinov, R. B. Dzhabbarov, O. B. Tagiev, N. N. Musaeva, and A. N. Georgobiani, “Synthesis and luminescent properties of ZnGa2S4:Eu,F and ZnGa2O4:Eu,F,” Inorg. Mater.36(12), 1189–1191 (2000).
[CrossRef]

Germain, G.

R. Roques, R. Rimet, J. P. Declercq, and G. Germain, “Determination of crystal-structure of EuGa2S4,” Acta Crystallogr. B35(3), 555–557 (1979).
[CrossRef]

Grill, W.

A. Eifler, G. Krauss, V. Riede, V. Kramer, and W. Grill, “Optical phonon modes and structure of ZnGa2Se4 and ZnGa2S4,” J. Phys. Chem. Solids66(11), 2052–2057 (2005).
[CrossRef]

Gruzintsev, A. N.

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

Guillen, F.

K. T. Lethi, A. Garcia, F. Guillen, and C. Fouassier, “Investigation of the MS-Al2S3 systems (M = Ca, Sr, Ba) and luminescence properties of europium-doped thioaluminates,” Mat. Sci. Eng. B-Solid14, 393–397 (1992).
[CrossRef]

Guseinov, G. G.

B. G. Tagiev, G. G. Guseinov, R. B. Dzhabbarov, O. B. Tagiev, N. N. Musaeva, and A. N. Georgobiani, “Synthesis and luminescent properties of ZnGa2S4:Eu,F and ZnGa2O4:Eu,F,” Inorg. Mater.36(12), 1189–1191 (2000).
[CrossRef]

Haeuseler, H.

C. Wickleder, S. Zhang, and H. Haeuseler, “Photoluminescence of ZnGa2S4:Eu2+,” Z. Kristallogr.220(2-3-2005), 277–280 (2005).
[CrossRef]

Hasnain, S. S.

G. Derbyshire, K. C. Cheung, P. Sangsingkeow, and S. S. Hasnain, “A low-profile monolithic multi-element Ge detector for X-ray fluorescence applications,” J. Synchrotron Radiat.6(2), 62–63 (1999).
[CrossRef]

Hintzen, H. T.

Y. Q. Li, C. M. Fang, G. de With, and H. T. Hintzen, “Preparation, structure and photoluminescence properties of Eu2+ and Ce3+-doped SrYSi4N7,” J. Solid State Chem.177(12), 4687–4694 (2004).
[CrossRef]

Hirosaki, N.

R. J. Xie, N. Hirosaki, Y. Q. Li, and T. Takeda, “Rare-earth activated nitride phosphors: synthesis, luminescence and applications,” Materials3(6), 3777–3793 (2010).
[CrossRef]

R. J. Xie, N. Hirosaki, and T. Takeda, “Wide color gamut backlight for liquid crystal displays using three-band phosphor-converted white light-emitting diodes,” Appl. Phys. Express2, 022401 (2009).
[CrossRef]

R. J. Xie, N. Hirosaki, H. L. Li, Y. Q. Li, and M. Mitomo, “Synthesis and photoluminescence properties of beta-sialon: Eu2+ (Si6-zAlzOzN8-z:Eu2+),” J. Electrochem. Soc.154, J314–J319 (2007).
[CrossRef]

Holt, D. B.

B. G. Yacobi and D. B. Holt, “Cathodoluminescence scanning electron-microscopy of semiconductors,” J. Appl. Phys.59(4), R1–R24 (1986).
[CrossRef]

Honma, T.

Y. Shimomura, T. Honma, M. Shigeiwa, T. Akai, K. Okamoto, and N. Kijima, “Photoluminescence and crystal structure of green-emitting Ca3Sc2Si3O12:Ce3+ phosphor for white light emitting diodes,” J. Electrochem. Soc.154(1), J35–J38 (2007).
[CrossRef]

Hoppe, H. A.

R. Mueller-Mach, G. Mueller, M. R. Krames, H. A. Hoppe, F. Stadler, W. Schnick, T. Juestel, and P. Schmidt, “Highly efficient all-nitride phosphor-converted white light emitting diode,” Physica Status Solidi a-Applications and Materials Science202(9), 1727–1732 (2005).
[CrossRef]

Höppe, H. A.

H. A. Höppe, “Recent developments in the field of inorganic phosphors,” Angew. Chem. Int. Ed. Engl.48(20), 3572–3582 (2009).
[CrossRef] [PubMed]

Huang, C. H.

Iida, S.

S. Iida, A. Kato, M. Tanaka, H. Najafov, and H. Ikuno, “Photoluminescence characterization of rare-earth stoichiometric compounds of EuGa2S4,” J. Phys. Chem. Solids64(9-10), 1815–1819 (2003).
[CrossRef]

Ikuno, H.

S. Iida, A. Kato, M. Tanaka, H. Najafov, and H. Ikuno, “Photoluminescence characterization of rare-earth stoichiometric compounds of EuGa2S4,” J. Phys. Chem. Solids64(9-10), 1815–1819 (2003).
[CrossRef]

Jabbarov, R. B.

R. B. Jabbarov, C. Chartier, B. G. Tagiev, O. B. Tagiev, N. N. Musayeva, C. Barthou, and P. Benalloul, “Radiative properties of Eu2+ in BaGa2S4,” J. Phys. Chem. Solids66(6), 1049–1056 (2005).
[CrossRef]

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

Jang, S. M.

Jeong, J. H.

R. Yu, R. X. Luan, C. F. Wang, J. T. Chen, Z. X. Wang, B. K. Moon, and J. H. Jeong, “Photoluminescence properties of green emitting ZnGa2S4:Eu2+ phosphor,” J. Electrochem. Soc.159(5), J188–J192 (2012).
[CrossRef]

R. J. Yu, H. K. Yang, B. K. Moon, B. C. Choi, and J. H. Jeong, “Luminescence properties of stoichiometric EuM2S4 (M = Ga, Al) conversion phosphors for white LED applications,” Physica Status Solidi a-Applications and Materials Science209(12), 2620–2625 (2012).
[CrossRef]

Jeong, Y. K.

Y. K. Jeong, D. H. Cho, K. B. Kim, and J. G. Kang, “Highly luminescent (Zn0.6Sr0.3Mg0.1)2Ga2S5:Eu2+ green phosphors for a white light-emitting diode,” Bull. Korean Chem. Soc.33(8), 2523–2528 (2012).
[CrossRef]

Y. K. Kim, D. H. Cho, Y. K. Jeong, M. K. Nah, K. B. Kim, and J. G. Kang, “Luminescence characterization of (Ca1-xZnx)Ga2S4:Eu2+ phosphors for a white light-emitting diode,” Mater. Res. Bull.45(8), 905–909 (2010).
[CrossRef]

Joos, J. J.

J. J. Joos, K. W. Meert, A. B. Parmentier, D. Poelman, and P. F. Smet, “Thermal quenching and luminescence lifetime of saturated green Sr1-xEuxGa2S4 phosphors,” Opt. Mater.34(11), 1902–1907 (2012).
[CrossRef]

Juestel, T.

R. Mueller-Mach, G. Mueller, M. R. Krames, H. A. Hoppe, F. Stadler, W. Schnick, T. Juestel, and P. Schmidt, “Highly efficient all-nitride phosphor-converted white light emitting diode,” Physica Status Solidi a-Applications and Materials Science202(9), 1727–1732 (2005).
[CrossRef]

Justel, T.

V. Bachmann, T. Justel, A. Meijerink, C. Ronda, and P. J. Schmidt, “Luminescence properties of SrSi2O2N2 doped with divalent rare earth ions,” J. Lumin.121(2), 441–449 (2006).
[CrossRef]

Kang, J. G.

Y. K. Jeong, D. H. Cho, K. B. Kim, and J. G. Kang, “Highly luminescent (Zn0.6Sr0.3Mg0.1)2Ga2S5:Eu2+ green phosphors for a white light-emitting diode,” Bull. Korean Chem. Soc.33(8), 2523–2528 (2012).
[CrossRef]

Y. K. Kim, D. H. Cho, Y. K. Jeong, M. K. Nah, K. B. Kim, and J. G. Kang, “Luminescence characterization of (Ca1-xZnx)Ga2S4:Eu2+ phosphors for a white light-emitting diode,” Mater. Res. Bull.45(8), 905–909 (2010).
[CrossRef]

Kato, A.

S. Iida, A. Kato, M. Tanaka, H. Najafov, and H. Ikuno, “Photoluminescence characterization of rare-earth stoichiometric compounds of EuGa2S4,” J. Phys. Chem. Solids64(9-10), 1815–1819 (2003).
[CrossRef]

Kijima, N.

Y. Shimomura, T. Honma, M. Shigeiwa, T. Akai, K. Okamoto, and N. Kijima, “Photoluminescence and crystal structure of green-emitting Ca3Sc2Si3O12:Ce3+ phosphor for white light emitting diodes,” J. Electrochem. Soc.154(1), J35–J38 (2007).
[CrossRef]

Kim, J. W.

J. W. Kim and Y. J. Kim, “Synthesis and luminescent characterization of zinc thiogallate,” J. Eur. Ceram. Soc.27(13-15), 3667–3670 (2007).
[CrossRef]

J. W. Kim and Y. J. Kim, “Optical properties of eu doped M-Ga2S4 (M: Zn, Ca, Sr) phosphors for white light emitting diodes,” J. Nanosci. Nanotechnol.7(11), 4065–4068 (2007).
[CrossRef] [PubMed]

Kim, K. B.

Y. K. Jeong, D. H. Cho, K. B. Kim, and J. G. Kang, “Highly luminescent (Zn0.6Sr0.3Mg0.1)2Ga2S5:Eu2+ green phosphors for a white light-emitting diode,” Bull. Korean Chem. Soc.33(8), 2523–2528 (2012).
[CrossRef]

Y. K. Kim, D. H. Cho, Y. K. Jeong, M. K. Nah, K. B. Kim, and J. G. Kang, “Luminescence characterization of (Ca1-xZnx)Ga2S4:Eu2+ phosphors for a white light-emitting diode,” Mater. Res. Bull.45(8), 905–909 (2010).
[CrossRef]

Kim, Y. J.

J. W. Kim and Y. J. Kim, “Optical properties of eu doped M-Ga2S4 (M: Zn, Ca, Sr) phosphors for white light emitting diodes,” J. Nanosci. Nanotechnol.7(11), 4065–4068 (2007).
[CrossRef] [PubMed]

J. W. Kim and Y. J. Kim, “Synthesis and luminescent characterization of zinc thiogallate,” J. Eur. Ceram. Soc.27(13-15), 3667–3670 (2007).
[CrossRef]

Kim, Y. K.

Y. K. Kim, D. H. Cho, Y. K. Jeong, M. K. Nah, K. B. Kim, and J. G. Kang, “Luminescence characterization of (Ca1-xZnx)Ga2S4:Eu2+ phosphors for a white light-emitting diode,” Mater. Res. Bull.45(8), 905–909 (2010).
[CrossRef]

Kobayashi, T.

T. Kobayashi, K. Susa, and S. Taniguchi, “Preparation and semiconductive properties of rock salt type solid-solution systems, Cd1-xMxS (M=Sr, Ca, Mg, Pb, Sn),” J. Phys. Chem. Solids40(10), 781–785 (1979).
[CrossRef]

Korthout, K.

K. Korthout, A. B. Parmentier, P. F. Smet, and D. Poelman, “A XAS study of the luminescent Eu centers in thiosilicate phosphors,” Phys. Chem. Chem. Phys.15(22), 8678–8683 (2013).
[CrossRef] [PubMed]

N. Avci, K. Korthout, M. A. Newton, P. F. Smet, and D. Poelman, “Valence states of europium in CaAl2O4:Eu phosphors,” Opt. Mater. Express2(3), 321–330 (2012).
[CrossRef]

Kramer, V.

A. Eifler, G. Krauss, V. Riede, V. Kramer, and W. Grill, “Optical phonon modes and structure of ZnGa2Se4 and ZnGa2S4,” J. Phys. Chem. Solids66(11), 2052–2057 (2005).
[CrossRef]

Krames, M. R.

R. Mueller-Mach, G. Mueller, M. R. Krames, H. A. Hoppe, F. Stadler, W. Schnick, T. Juestel, and P. Schmidt, “Highly efficient all-nitride phosphor-converted white light emitting diode,” Physica Status Solidi a-Applications and Materials Science202(9), 1727–1732 (2005).
[CrossRef]

Krauss, G.

A. Eifler, G. Krauss, V. Riede, V. Kramer, and W. Grill, “Optical phonon modes and structure of ZnGa2Se4 and ZnGa2S4,” J. Phys. Chem. Solids66(11), 2052–2057 (2005).
[CrossRef]

Lee, S. J.

Lee, T. J.

Lepnev, L. S.

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

Lethi, K. T.

K. T. Lethi, A. Garcia, F. Guillen, and C. Fouassier, “Investigation of the MS-Al2S3 systems (M = Ca, Sr, Ba) and luminescence properties of europium-doped thioaluminates,” Mat. Sci. Eng. B-Solid14, 393–397 (1992).
[CrossRef]

Li, H. L.

R. J. Xie, N. Hirosaki, H. L. Li, Y. Q. Li, and M. Mitomo, “Synthesis and photoluminescence properties of beta-sialon: Eu2+ (Si6-zAlzOzN8-z:Eu2+),” J. Electrochem. Soc.154, J314–J319 (2007).
[CrossRef]

Li, Y. Q.

R. J. Xie, N. Hirosaki, Y. Q. Li, and T. Takeda, “Rare-earth activated nitride phosphors: synthesis, luminescence and applications,” Materials3(6), 3777–3793 (2010).
[CrossRef]

R. J. Xie, N. Hirosaki, H. L. Li, Y. Q. Li, and M. Mitomo, “Synthesis and photoluminescence properties of beta-sialon: Eu2+ (Si6-zAlzOzN8-z:Eu2+),” J. Electrochem. Soc.154, J314–J319 (2007).
[CrossRef]

Y. Q. Li, C. M. Fang, G. de With, and H. T. Hintzen, “Preparation, structure and photoluminescence properties of Eu2+ and Ce3+-doped SrYSi4N7,” J. Solid State Chem.177(12), 4687–4694 (2004).
[CrossRef]

Liu, R. S.

Liu, W. R.

Lowe-Ma, C. K.

C. K. Lowe-Ma and T. A. Vanderah, “Structure of ZnGa2S4, a defect sphalerite derivative,” Acta Crystallogr. C47(5), 919–924 (1991).
[CrossRef]

Luan, R. X.

R. Yu, R. X. Luan, C. F. Wang, J. T. Chen, Z. X. Wang, B. K. Moon, and J. H. Jeong, “Photoluminescence properties of green emitting ZnGa2S4:Eu2+ phosphor,” J. Electrochem. Soc.159(5), J188–J192 (2012).
[CrossRef]

Maak, C.

M. Seibald, T. Rosenthal, O. Oeckler, C. Maak, A. Tücks, P. J. Schmidt, D. Wiechert, and W. Schnick, “New polymorph of the highly efficient LED-phosphor SrSi2O2N2:Eu2+ – polytypism of a layered oxonitridosilicate,” Chem. Mater.25(9), 1852–1857 (2013).
[CrossRef]

Meert, K. W.

J. J. Joos, K. W. Meert, A. B. Parmentier, D. Poelman, and P. F. Smet, “Thermal quenching and luminescence lifetime of saturated green Sr1-xEuxGa2S4 phosphors,” Opt. Mater.34(11), 1902–1907 (2012).
[CrossRef]

Meijerink, A.

V. Bachmann, C. Ronda, and A. Meijerink, “Temperature quenching of yellow Ce3+ luminescence in YAG:Ce,” Chem. Mater.21(10), 2077–2084 (2009).
[CrossRef]

V. Bachmann, C. Ronda, O. Oeckler, W. Schnick, and A. Meijerink, “Color point tuning for (Sr,Ca,Ba)Si2O2N2:Eu2+ for white light LEDs,” Chem. Mater.21(2), 316–325 (2009).
[CrossRef]

V. Bachmann, T. Justel, A. Meijerink, C. Ronda, and P. J. Schmidt, “Luminescence properties of SrSi2O2N2 doped with divalent rare earth ions,” J. Lumin.121(2), 441–449 (2006).
[CrossRef]

Meyerink, A.

S. H. M. Poort, A. Meyerink, and G. Blasse, “Lifetime measurements in Eu2+-doped host lattices,” J. Phys. Chem. Solids58(9), 1451–1456 (1997).
[CrossRef]

Miehe, G.

C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
[CrossRef] [PubMed]

Mitomo, M.

R. J. Xie, N. Hirosaki, H. L. Li, Y. Q. Li, and M. Mitomo, “Synthesis and photoluminescence properties of beta-sialon: Eu2+ (Si6-zAlzOzN8-z:Eu2+),” J. Electrochem. Soc.154, J314–J319 (2007).
[CrossRef]

Moewes, A.

C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
[CrossRef] [PubMed]

Moon, B. K.

R. J. Yu, H. K. Yang, B. K. Moon, B. C. Choi, and J. H. Jeong, “Luminescence properties of stoichiometric EuM2S4 (M = Ga, Al) conversion phosphors for white LED applications,” Physica Status Solidi a-Applications and Materials Science209(12), 2620–2625 (2012).
[CrossRef]

R. Yu, R. X. Luan, C. F. Wang, J. T. Chen, Z. X. Wang, B. K. Moon, and J. H. Jeong, “Photoluminescence properties of green emitting ZnGa2S4:Eu2+ phosphor,” J. Electrochem. Soc.159(5), J188–J192 (2012).
[CrossRef]

Mueller, G.

R. Mueller-Mach, G. Mueller, M. R. Krames, H. A. Hoppe, F. Stadler, W. Schnick, T. Juestel, and P. Schmidt, “Highly efficient all-nitride phosphor-converted white light emitting diode,” Physica Status Solidi a-Applications and Materials Science202(9), 1727–1732 (2005).
[CrossRef]

Mueller-Mach, R.

R. Mueller-Mach, G. Mueller, M. R. Krames, H. A. Hoppe, F. Stadler, W. Schnick, T. Juestel, and P. Schmidt, “Highly efficient all-nitride phosphor-converted white light emitting diode,” Physica Status Solidi a-Applications and Materials Science202(9), 1727–1732 (2005).
[CrossRef]

Musaeva, N. N.

B. G. Tagiev, G. G. Guseinov, R. B. Dzhabbarov, O. B. Tagiev, N. N. Musaeva, and A. N. Georgobiani, “Synthesis and luminescent properties of ZnGa2S4:Eu,F and ZnGa2O4:Eu,F,” Inorg. Mater.36(12), 1189–1191 (2000).
[CrossRef]

Musayeva, N. N.

R. B. Jabbarov, C. Chartier, B. G. Tagiev, O. B. Tagiev, N. N. Musayeva, C. Barthou, and P. Benalloul, “Radiative properties of Eu2+ in BaGa2S4,” J. Phys. Chem. Solids66(6), 1049–1056 (2005).
[CrossRef]

Nah, M. K.

Y. K. Kim, D. H. Cho, Y. K. Jeong, M. K. Nah, K. B. Kim, and J. G. Kang, “Luminescence characterization of (Ca1-xZnx)Ga2S4:Eu2+ phosphors for a white light-emitting diode,” Mater. Res. Bull.45(8), 905–909 (2010).
[CrossRef]

Najafov, H.

S. Iida, A. Kato, M. Tanaka, H. Najafov, and H. Ikuno, “Photoluminescence characterization of rare-earth stoichiometric compounds of EuGa2S4,” J. Phys. Chem. Solids64(9-10), 1815–1819 (2003).
[CrossRef]

Newton, M. A.

Newville, M.

B. Ravel and M. Newville, “ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT,” J. Synchrotron Radiat.12(4), 537–541 (2005).
[CrossRef] [PubMed]

Oeckler, O.

M. Seibald, T. Rosenthal, O. Oeckler, C. Maak, A. Tücks, P. J. Schmidt, D. Wiechert, and W. Schnick, “New polymorph of the highly efficient LED-phosphor SrSi2O2N2:Eu2+ – polytypism of a layered oxonitridosilicate,” Chem. Mater.25(9), 1852–1857 (2013).
[CrossRef]

C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
[CrossRef] [PubMed]

V. Bachmann, C. Ronda, O. Oeckler, W. Schnick, and A. Meijerink, “Color point tuning for (Sr,Ca,Ba)Si2O2N2:Eu2+ for white light LEDs,” Chem. Mater.21(2), 316–325 (2009).
[CrossRef]

Oh, J. H.

Okamoto, K.

Y. Shimomura, T. Honma, M. Shigeiwa, T. Akai, K. Okamoto, and N. Kijima, “Photoluminescence and crystal structure of green-emitting Ca3Sc2Si3O12:Ce3+ phosphor for white light emitting diodes,” J. Electrochem. Soc.154(1), J35–J38 (2007).
[CrossRef]

Parmentier, A. B.

K. Korthout, A. B. Parmentier, P. F. Smet, and D. Poelman, “A XAS study of the luminescent Eu centers in thiosilicate phosphors,” Phys. Chem. Chem. Phys.15(22), 8678–8683 (2013).
[CrossRef] [PubMed]

J. J. Joos, K. W. Meert, A. B. Parmentier, D. Poelman, and P. F. Smet, “Thermal quenching and luminescence lifetime of saturated green Sr1-xEuxGa2S4 phosphors,” Opt. Mater.34(11), 1902–1907 (2012).
[CrossRef]

P. F. Smet, A. B. Parmentier, and D. Poelman, “Selecting conversion phosphors for white light-emitting diodes,” J. Electrochem. Soc.158(6), R37–R54 (2011).
[CrossRef]

A. B. Parmentier, P. F. Smet, F. Bertram, J. Christen, and D. Poelman, “Structure and luminescence of (Ca,Sr)2SiS4:Eu2+ phosphors,” J. Phys. D Appl. Phys.43(8), 085401 (2010).
[CrossRef]

Poelman, D.

K. Korthout, A. B. Parmentier, P. F. Smet, and D. Poelman, “A XAS study of the luminescent Eu centers in thiosilicate phosphors,” Phys. Chem. Chem. Phys.15(22), 8678–8683 (2013).
[CrossRef] [PubMed]

N. Avci, K. Korthout, M. A. Newton, P. F. Smet, and D. Poelman, “Valence states of europium in CaAl2O4:Eu phosphors,” Opt. Mater. Express2(3), 321–330 (2012).
[CrossRef]

J. J. Joos, K. W. Meert, A. B. Parmentier, D. Poelman, and P. F. Smet, “Thermal quenching and luminescence lifetime of saturated green Sr1-xEuxGa2S4 phosphors,” Opt. Mater.34(11), 1902–1907 (2012).
[CrossRef]

P. F. Smet, A. B. Parmentier, and D. Poelman, “Selecting conversion phosphors for white light-emitting diodes,” J. Electrochem. Soc.158(6), R37–R54 (2011).
[CrossRef]

A. B. Parmentier, P. F. Smet, F. Bertram, J. Christen, and D. Poelman, “Structure and luminescence of (Ca,Sr)2SiS4:Eu2+ phosphors,” J. Phys. D Appl. Phys.43(8), 085401 (2010).
[CrossRef]

J. E. Van Haecke, P. F. Smet, and D. Poelman, “Luminescent characterization of CaAl2S4:Eu powder,” J. Lumin.126(2), 508–514 (2007).
[CrossRef]

P. F. Smet, J. E. Van Haecke, R. L. Van Meirhaeghe, and D. Poelman, “Crystallographic and luminescent properties of orthorhombic BaAl2S4:Eu powder and thin films,” J. Appl. Phys.98(4), 043512 (2005).
[CrossRef]

Poort, S. H. M.

S. H. M. Poort, A. Meyerink, and G. Blasse, “Lifetime measurements in Eu2+-doped host lattices,” J. Phys. Chem. Solids58(9), 1451–1456 (1997).
[CrossRef]

Ravel, B.

B. Ravel and M. Newville, “ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT,” J. Synchrotron Radiat.12(4), 537–541 (2005).
[CrossRef] [PubMed]

Riede, V.

A. Eifler, G. Krauss, V. Riede, V. Kramer, and W. Grill, “Optical phonon modes and structure of ZnGa2Se4 and ZnGa2S4,” J. Phys. Chem. Solids66(11), 2052–2057 (2005).
[CrossRef]

Rimet, R.

R. Roques, R. Rimet, J. P. Declercq, and G. Germain, “Determination of crystal-structure of EuGa2S4,” Acta Crystallogr. B35(3), 555–557 (1979).
[CrossRef]

Ronda, C.

V. Bachmann, C. Ronda, O. Oeckler, W. Schnick, and A. Meijerink, “Color point tuning for (Sr,Ca,Ba)Si2O2N2:Eu2+ for white light LEDs,” Chem. Mater.21(2), 316–325 (2009).
[CrossRef]

V. Bachmann, C. Ronda, and A. Meijerink, “Temperature quenching of yellow Ce3+ luminescence in YAG:Ce,” Chem. Mater.21(10), 2077–2084 (2009).
[CrossRef]

V. Bachmann, T. Justel, A. Meijerink, C. Ronda, and P. J. Schmidt, “Luminescence properties of SrSi2O2N2 doped with divalent rare earth ions,” J. Lumin.121(2), 441–449 (2006).
[CrossRef]

Roques, R.

R. Roques, R. Rimet, J. P. Declercq, and G. Germain, “Determination of crystal-structure of EuGa2S4,” Acta Crystallogr. B35(3), 555–557 (1979).
[CrossRef]

Rosenthal, T.

M. Seibald, T. Rosenthal, O. Oeckler, C. Maak, A. Tücks, P. J. Schmidt, D. Wiechert, and W. Schnick, “New polymorph of the highly efficient LED-phosphor SrSi2O2N2:Eu2+ – polytypism of a layered oxonitridosilicate,” Chem. Mater.25(9), 1852–1857 (2013).
[CrossRef]

Sangsingkeow, P.

G. Derbyshire, K. C. Cheung, P. Sangsingkeow, and S. S. Hasnain, “A low-profile monolithic multi-element Ge detector for X-ray fluorescence applications,” J. Synchrotron Radiat.6(2), 62–63 (1999).
[CrossRef]

Schmidt, P.

R. Mueller-Mach, G. Mueller, M. R. Krames, H. A. Hoppe, F. Stadler, W. Schnick, T. Juestel, and P. Schmidt, “Highly efficient all-nitride phosphor-converted white light emitting diode,” Physica Status Solidi a-Applications and Materials Science202(9), 1727–1732 (2005).
[CrossRef]

Schmidt, P. J.

M. Seibald, T. Rosenthal, O. Oeckler, C. Maak, A. Tücks, P. J. Schmidt, D. Wiechert, and W. Schnick, “New polymorph of the highly efficient LED-phosphor SrSi2O2N2:Eu2+ – polytypism of a layered oxonitridosilicate,” Chem. Mater.25(9), 1852–1857 (2013).
[CrossRef]

V. Bachmann, T. Justel, A. Meijerink, C. Ronda, and P. J. Schmidt, “Luminescence properties of SrSi2O2N2 doped with divalent rare earth ions,” J. Lumin.121(2), 441–449 (2006).
[CrossRef]

Schnick, W.

M. Seibald, T. Rosenthal, O. Oeckler, C. Maak, A. Tücks, P. J. Schmidt, D. Wiechert, and W. Schnick, “New polymorph of the highly efficient LED-phosphor SrSi2O2N2:Eu2+ – polytypism of a layered oxonitridosilicate,” Chem. Mater.25(9), 1852–1857 (2013).
[CrossRef]

C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
[CrossRef] [PubMed]

V. Bachmann, C. Ronda, O. Oeckler, W. Schnick, and A. Meijerink, “Color point tuning for (Sr,Ca,Ba)Si2O2N2:Eu2+ for white light LEDs,” Chem. Mater.21(2), 316–325 (2009).
[CrossRef]

R. Mueller-Mach, G. Mueller, M. R. Krames, H. A. Hoppe, F. Stadler, W. Schnick, T. Juestel, and P. Schmidt, “Highly efficient all-nitride phosphor-converted white light emitting diode,” Physica Status Solidi a-Applications and Materials Science202(9), 1727–1732 (2005).
[CrossRef]

Seibald, M.

M. Seibald, T. Rosenthal, O. Oeckler, C. Maak, A. Tücks, P. J. Schmidt, D. Wiechert, and W. Schnick, “New polymorph of the highly efficient LED-phosphor SrSi2O2N2:Eu2+ – polytypism of a layered oxonitridosilicate,” Chem. Mater.25(9), 1852–1857 (2013).
[CrossRef]

C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
[CrossRef] [PubMed]

Shannon, R. D.

R. D. Shannon, “Revised effective ionic-radii and systematic studies of interatomic distances in halides and chalcogenides,” Acta Crystallogr. A32(5), 751–767 (1976).
[CrossRef]

Shigeiwa, M.

Y. Shimomura, T. Honma, M. Shigeiwa, T. Akai, K. Okamoto, and N. Kijima, “Photoluminescence and crystal structure of green-emitting Ca3Sc2Si3O12:Ce3+ phosphor for white light emitting diodes,” J. Electrochem. Soc.154(1), J35–J38 (2007).
[CrossRef]

Shimomura, Y.

Y. Shimomura, T. Honma, M. Shigeiwa, T. Akai, K. Okamoto, and N. Kijima, “Photoluminescence and crystal structure of green-emitting Ca3Sc2Si3O12:Ce3+ phosphor for white light emitting diodes,” J. Electrochem. Soc.154(1), J35–J38 (2007).
[CrossRef]

Smet, P. F.

K. Korthout, A. B. Parmentier, P. F. Smet, and D. Poelman, “A XAS study of the luminescent Eu centers in thiosilicate phosphors,” Phys. Chem. Chem. Phys.15(22), 8678–8683 (2013).
[CrossRef] [PubMed]

N. Avci, K. Korthout, M. A. Newton, P. F. Smet, and D. Poelman, “Valence states of europium in CaAl2O4:Eu phosphors,” Opt. Mater. Express2(3), 321–330 (2012).
[CrossRef]

J. J. Joos, K. W. Meert, A. B. Parmentier, D. Poelman, and P. F. Smet, “Thermal quenching and luminescence lifetime of saturated green Sr1-xEuxGa2S4 phosphors,” Opt. Mater.34(11), 1902–1907 (2012).
[CrossRef]

P. F. Smet, A. B. Parmentier, and D. Poelman, “Selecting conversion phosphors for white light-emitting diodes,” J. Electrochem. Soc.158(6), R37–R54 (2011).
[CrossRef]

A. B. Parmentier, P. F. Smet, F. Bertram, J. Christen, and D. Poelman, “Structure and luminescence of (Ca,Sr)2SiS4:Eu2+ phosphors,” J. Phys. D Appl. Phys.43(8), 085401 (2010).
[CrossRef]

J. E. Van Haecke, P. F. Smet, and D. Poelman, “Luminescent characterization of CaAl2S4:Eu powder,” J. Lumin.126(2), 508–514 (2007).
[CrossRef]

P. F. Smet, J. E. Van Haecke, R. L. Van Meirhaeghe, and D. Poelman, “Crystallographic and luminescent properties of orthorhombic BaAl2S4:Eu powder and thin films,” J. Appl. Phys.98(4), 043512 (2005).
[CrossRef]

Stadler, F.

R. Mueller-Mach, G. Mueller, M. R. Krames, H. A. Hoppe, F. Stadler, W. Schnick, T. Juestel, and P. Schmidt, “Highly efficient all-nitride phosphor-converted white light emitting diode,” Physica Status Solidi a-Applications and Materials Science202(9), 1727–1732 (2005).
[CrossRef]

Suh, D. W.

Sung, Y. G.

Susa, K.

T. Kobayashi, K. Susa, and S. Taniguchi, “Preparation and semiconductive properties of rock salt type solid-solution systems, Cd1-xMxS (M=Sr, Ca, Mg, Pb, Sn),” J. Phys. Chem. Solids40(10), 781–785 (1979).
[CrossRef]

Tagiev, B. G.

R. B. Jabbarov, C. Chartier, B. G. Tagiev, O. B. Tagiev, N. N. Musayeva, C. Barthou, and P. Benalloul, “Radiative properties of Eu2+ in BaGa2S4,” J. Phys. Chem. Solids66(6), 1049–1056 (2005).
[CrossRef]

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

B. G. Tagiev, G. G. Guseinov, R. B. Dzhabbarov, O. B. Tagiev, N. N. Musaeva, and A. N. Georgobiani, “Synthesis and luminescent properties of ZnGa2S4:Eu,F and ZnGa2O4:Eu,F,” Inorg. Mater.36(12), 1189–1191 (2000).
[CrossRef]

Tagiev, O. B.

R. B. Jabbarov, C. Chartier, B. G. Tagiev, O. B. Tagiev, N. N. Musayeva, C. Barthou, and P. Benalloul, “Radiative properties of Eu2+ in BaGa2S4,” J. Phys. Chem. Solids66(6), 1049–1056 (2005).
[CrossRef]

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

B. G. Tagiev, G. G. Guseinov, R. B. Dzhabbarov, O. B. Tagiev, N. N. Musaeva, and A. N. Georgobiani, “Synthesis and luminescent properties of ZnGa2S4:Eu,F and ZnGa2O4:Eu,F,” Inorg. Mater.36(12), 1189–1191 (2000).
[CrossRef]

Takeda, T.

R. J. Xie, N. Hirosaki, Y. Q. Li, and T. Takeda, “Rare-earth activated nitride phosphors: synthesis, luminescence and applications,” Materials3(6), 3777–3793 (2010).
[CrossRef]

R. J. Xie, N. Hirosaki, and T. Takeda, “Wide color gamut backlight for liquid crystal displays using three-band phosphor-converted white light-emitting diodes,” Appl. Phys. Express2, 022401 (2009).
[CrossRef]

Tanaka, M.

S. Iida, A. Kato, M. Tanaka, H. Najafov, and H. Ikuno, “Photoluminescence characterization of rare-earth stoichiometric compounds of EuGa2S4,” J. Phys. Chem. Solids64(9-10), 1815–1819 (2003).
[CrossRef]

Taniguchi, S.

T. Kobayashi, K. Susa, and S. Taniguchi, “Preparation and semiconductive properties of rock salt type solid-solution systems, Cd1-xMxS (M=Sr, Ca, Mg, Pb, Sn),” J. Phys. Chem. Solids40(10), 781–785 (1979).
[CrossRef]

Tücks, A.

M. Seibald, T. Rosenthal, O. Oeckler, C. Maak, A. Tücks, P. J. Schmidt, D. Wiechert, and W. Schnick, “New polymorph of the highly efficient LED-phosphor SrSi2O2N2:Eu2+ – polytypism of a layered oxonitridosilicate,” Chem. Mater.25(9), 1852–1857 (2013).
[CrossRef]

C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
[CrossRef] [PubMed]

Van Haecke, J. E.

J. E. Van Haecke, P. F. Smet, and D. Poelman, “Luminescent characterization of CaAl2S4:Eu powder,” J. Lumin.126(2), 508–514 (2007).
[CrossRef]

P. F. Smet, J. E. Van Haecke, R. L. Van Meirhaeghe, and D. Poelman, “Crystallographic and luminescent properties of orthorhombic BaAl2S4:Eu powder and thin films,” J. Appl. Phys.98(4), 043512 (2005).
[CrossRef]

Van Meirhaeghe, R. L.

P. F. Smet, J. E. Van Haecke, R. L. Van Meirhaeghe, and D. Poelman, “Crystallographic and luminescent properties of orthorhombic BaAl2S4:Eu powder and thin films,” J. Appl. Phys.98(4), 043512 (2005).
[CrossRef]

Vanderah, T. A.

C. K. Lowe-Ma and T. A. Vanderah, “Structure of ZnGa2S4, a defect sphalerite derivative,” Acta Crystallogr. C47(5), 919–924 (1991).
[CrossRef]

Wang, C. F.

R. Yu, R. X. Luan, C. F. Wang, J. T. Chen, Z. X. Wang, B. K. Moon, and J. H. Jeong, “Photoluminescence properties of green emitting ZnGa2S4:Eu2+ phosphor,” J. Electrochem. Soc.159(5), J188–J192 (2012).
[CrossRef]

Wang, Z. X.

R. Yu, R. X. Luan, C. F. Wang, J. T. Chen, Z. X. Wang, B. K. Moon, and J. H. Jeong, “Photoluminescence properties of green emitting ZnGa2S4:Eu2+ phosphor,” J. Electrochem. Soc.159(5), J188–J192 (2012).
[CrossRef]

White, W. B.

M. M. Yuta and W. B. White, “Photoluminescence of sulfide phosphors with the MB2S4 composition,” J. Electrochem. Soc.139(8), 2347–2352 (1992).
[CrossRef]

Wickleder, C.

C. Wickleder, S. Zhang, and H. Haeuseler, “Photoluminescence of ZnGa2S4:Eu2+,” Z. Kristallogr.220(2-3-2005), 277–280 (2005).
[CrossRef]

Wiechert, D.

M. Seibald, T. Rosenthal, O. Oeckler, C. Maak, A. Tücks, P. J. Schmidt, D. Wiechert, and W. Schnick, “New polymorph of the highly efficient LED-phosphor SrSi2O2N2:Eu2+ – polytypism of a layered oxonitridosilicate,” Chem. Mater.25(9), 1852–1857 (2013).
[CrossRef]

Xie, R. J.

R. J. Xie, N. Hirosaki, Y. Q. Li, and T. Takeda, “Rare-earth activated nitride phosphors: synthesis, luminescence and applications,” Materials3(6), 3777–3793 (2010).
[CrossRef]

R. J. Xie, N. Hirosaki, and T. Takeda, “Wide color gamut backlight for liquid crystal displays using three-band phosphor-converted white light-emitting diodes,” Appl. Phys. Express2, 022401 (2009).
[CrossRef]

R. J. Xie, N. Hirosaki, H. L. Li, Y. Q. Li, and M. Mitomo, “Synthesis and photoluminescence properties of beta-sialon: Eu2+ (Si6-zAlzOzN8-z:Eu2+),” J. Electrochem. Soc.154, J314–J319 (2007).
[CrossRef]

Yacobi, B. G.

B. G. Yacobi and D. B. Holt, “Cathodoluminescence scanning electron-microscopy of semiconductors,” J. Appl. Phys.59(4), R1–R24 (1986).
[CrossRef]

Yang, H. K.

R. J. Yu, H. K. Yang, B. K. Moon, B. C. Choi, and J. H. Jeong, “Luminescence properties of stoichiometric EuM2S4 (M = Ga, Al) conversion phosphors for white LED applications,” Physica Status Solidi a-Applications and Materials Science209(12), 2620–2625 (2012).
[CrossRef]

Yang, S. J.

Yeh, Y. T.

Yoo, J. S.

Yu, R.

R. Yu, R. X. Luan, C. F. Wang, J. T. Chen, Z. X. Wang, B. K. Moon, and J. H. Jeong, “Photoluminescence properties of green emitting ZnGa2S4:Eu2+ phosphor,” J. Electrochem. Soc.159(5), J188–J192 (2012).
[CrossRef]

Yu, R. J.

R. J. Yu, H. K. Yang, B. K. Moon, B. C. Choi, and J. H. Jeong, “Luminescence properties of stoichiometric EuM2S4 (M = Ga, Al) conversion phosphors for white LED applications,” Physica Status Solidi a-Applications and Materials Science209(12), 2620–2625 (2012).
[CrossRef]

Yuta, M. M.

M. M. Yuta and W. B. White, “Photoluminescence of sulfide phosphors with the MB2S4 composition,” J. Electrochem. Soc.139(8), 2347–2352 (1992).
[CrossRef]

Zhang, S.

C. Wickleder, S. Zhang, and H. Haeuseler, “Photoluminescence of ZnGa2S4:Eu2+,” Z. Kristallogr.220(2-3-2005), 277–280 (2005).
[CrossRef]

Acta Crystallogr. A (1)

R. D. Shannon, “Revised effective ionic-radii and systematic studies of interatomic distances in halides and chalcogenides,” Acta Crystallogr. A32(5), 751–767 (1976).
[CrossRef]

Acta Crystallogr. B (1)

R. Roques, R. Rimet, J. P. Declercq, and G. Germain, “Determination of crystal-structure of EuGa2S4,” Acta Crystallogr. B35(3), 555–557 (1979).
[CrossRef]

Acta Crystallogr. C (1)

C. K. Lowe-Ma and T. A. Vanderah, “Structure of ZnGa2S4, a defect sphalerite derivative,” Acta Crystallogr. C47(5), 919–924 (1991).
[CrossRef]

Angew. Chem. Int. Ed. Engl. (1)

H. A. Höppe, “Recent developments in the field of inorganic phosphors,” Angew. Chem. Int. Ed. Engl.48(20), 3572–3582 (2009).
[CrossRef] [PubMed]

Appl. Phys. Express (1)

R. J. Xie, N. Hirosaki, and T. Takeda, “Wide color gamut backlight for liquid crystal displays using three-band phosphor-converted white light-emitting diodes,” Appl. Phys. Express2, 022401 (2009).
[CrossRef]

Bull. Korean Chem. Soc. (1)

Y. K. Jeong, D. H. Cho, K. B. Kim, and J. G. Kang, “Highly luminescent (Zn0.6Sr0.3Mg0.1)2Ga2S5:Eu2+ green phosphors for a white light-emitting diode,” Bull. Korean Chem. Soc.33(8), 2523–2528 (2012).
[CrossRef]

Chem. Mater. (3)

V. Bachmann, C. Ronda, and A. Meijerink, “Temperature quenching of yellow Ce3+ luminescence in YAG:Ce,” Chem. Mater.21(10), 2077–2084 (2009).
[CrossRef]

M. Seibald, T. Rosenthal, O. Oeckler, C. Maak, A. Tücks, P. J. Schmidt, D. Wiechert, and W. Schnick, “New polymorph of the highly efficient LED-phosphor SrSi2O2N2:Eu2+ – polytypism of a layered oxonitridosilicate,” Chem. Mater.25(9), 1852–1857 (2013).
[CrossRef]

V. Bachmann, C. Ronda, O. Oeckler, W. Schnick, and A. Meijerink, “Color point tuning for (Sr,Ca,Ba)Si2O2N2:Eu2+ for white light LEDs,” Chem. Mater.21(2), 316–325 (2009).
[CrossRef]

Chemistry (1)

C. Braun, M. Seibald, S. L. Börger, O. Oeckler, T. D. Boyko, A. Moewes, G. Miehe, A. Tücks, and W. Schnick, “Material properties and structural characterization of M3Si6O12N2:Eu2+ (M = Ba, Sr) - A comprehensive study on a promising green phosphor for pc-LEDs,” Chemistry16(31), 9646–9657 (2010).
[CrossRef] [PubMed]

IEEE J. Sel. Top. Quant. (1)

M. H. Crawford, “LEDs for solid-state lighting: performance challenges and recent advances,” IEEE J. Sel. Top. Quant.15(4), 1028–1040 (2009).
[CrossRef]

Inorg. Mater. (1)

B. G. Tagiev, G. G. Guseinov, R. B. Dzhabbarov, O. B. Tagiev, N. N. Musaeva, and A. N. Georgobiani, “Synthesis and luminescent properties of ZnGa2S4:Eu,F and ZnGa2O4:Eu,F,” Inorg. Mater.36(12), 1189–1191 (2000).
[CrossRef]

J. Appl. Phys. (2)

P. F. Smet, J. E. Van Haecke, R. L. Van Meirhaeghe, and D. Poelman, “Crystallographic and luminescent properties of orthorhombic BaAl2S4:Eu powder and thin films,” J. Appl. Phys.98(4), 043512 (2005).
[CrossRef]

B. G. Yacobi and D. B. Holt, “Cathodoluminescence scanning electron-microscopy of semiconductors,” J. Appl. Phys.59(4), R1–R24 (1986).
[CrossRef]

J. Electrochem. Soc. (7)

P. Benalloul, C. Barthou, C. Fouassier, A. N. Georgobiani, L. S. Lepnev, Y. N. Emirov, A. N. Gruzintsev, B. G. Tagiev, O. B. Tagiev, and R. B. Jabbarov, “Luminescence of Eu2+ in calcium thiogallate,” J. Electrochem. Soc.150(1), G62–G65 (2003).
[CrossRef]

R. Yu, R. X. Luan, C. F. Wang, J. T. Chen, Z. X. Wang, B. K. Moon, and J. H. Jeong, “Photoluminescence properties of green emitting ZnGa2S4:Eu2+ phosphor,” J. Electrochem. Soc.159(5), J188–J192 (2012).
[CrossRef]

M. M. Yuta and W. B. White, “Photoluminescence of sulfide phosphors with the MB2S4 composition,” J. Electrochem. Soc.139(8), 2347–2352 (1992).
[CrossRef]

P. F. Smet, A. B. Parmentier, and D. Poelman, “Selecting conversion phosphors for white light-emitting diodes,” J. Electrochem. Soc.158(6), R37–R54 (2011).
[CrossRef]

T. L. Barry, “Fluorescence of Eu2+-activated phases in binary alkaline earth orthosilicate systems,” J. Electrochem. Soc.115(11), 1181–1184 (1968).
[CrossRef]

Y. Shimomura, T. Honma, M. Shigeiwa, T. Akai, K. Okamoto, and N. Kijima, “Photoluminescence and crystal structure of green-emitting Ca3Sc2Si3O12:Ce3+ phosphor for white light emitting diodes,” J. Electrochem. Soc.154(1), J35–J38 (2007).
[CrossRef]

R. J. Xie, N. Hirosaki, H. L. Li, Y. Q. Li, and M. Mitomo, “Synthesis and photoluminescence properties of beta-sialon: Eu2+ (Si6-zAlzOzN8-z:Eu2+),” J. Electrochem. Soc.154, J314–J319 (2007).
[CrossRef]

J. Eur. Ceram. Soc. (1)

J. W. Kim and Y. J. Kim, “Synthesis and luminescent characterization of zinc thiogallate,” J. Eur. Ceram. Soc.27(13-15), 3667–3670 (2007).
[CrossRef]

J. Lumin. (3)

J. E. Van Haecke, P. F. Smet, and D. Poelman, “Luminescent characterization of CaAl2S4:Eu powder,” J. Lumin.126(2), 508–514 (2007).
[CrossRef]

V. Bachmann, T. Justel, A. Meijerink, C. Ronda, and P. J. Schmidt, “Luminescence properties of SrSi2O2N2 doped with divalent rare earth ions,” J. Lumin.121(2), 441–449 (2006).
[CrossRef]

P. Dorenbos, “Energy of the first 4f7-> 4f65d transition of Eu2+ in inorganic compounds,” J. Lumin.104(4), 239–260 (2003).
[CrossRef]

J. Nanosci. Nanotechnol. (1)

J. W. Kim and Y. J. Kim, “Optical properties of eu doped M-Ga2S4 (M: Zn, Ca, Sr) phosphors for white light emitting diodes,” J. Nanosci. Nanotechnol.7(11), 4065–4068 (2007).
[CrossRef] [PubMed]

J. Phys. Chem. Solids (5)

S. H. M. Poort, A. Meyerink, and G. Blasse, “Lifetime measurements in Eu2+-doped host lattices,” J. Phys. Chem. Solids58(9), 1451–1456 (1997).
[CrossRef]

R. B. Jabbarov, C. Chartier, B. G. Tagiev, O. B. Tagiev, N. N. Musayeva, C. Barthou, and P. Benalloul, “Radiative properties of Eu2+ in BaGa2S4,” J. Phys. Chem. Solids66(6), 1049–1056 (2005).
[CrossRef]

S. Iida, A. Kato, M. Tanaka, H. Najafov, and H. Ikuno, “Photoluminescence characterization of rare-earth stoichiometric compounds of EuGa2S4,” J. Phys. Chem. Solids64(9-10), 1815–1819 (2003).
[CrossRef]

A. Eifler, G. Krauss, V. Riede, V. Kramer, and W. Grill, “Optical phonon modes and structure of ZnGa2Se4 and ZnGa2S4,” J. Phys. Chem. Solids66(11), 2052–2057 (2005).
[CrossRef]

T. Kobayashi, K. Susa, and S. Taniguchi, “Preparation and semiconductive properties of rock salt type solid-solution systems, Cd1-xMxS (M=Sr, Ca, Mg, Pb, Sn),” J. Phys. Chem. Solids40(10), 781–785 (1979).
[CrossRef]

J. Phys. D Appl. Phys. (1)

A. B. Parmentier, P. F. Smet, F. Bertram, J. Christen, and D. Poelman, “Structure and luminescence of (Ca,Sr)2SiS4:Eu2+ phosphors,” J. Phys. D Appl. Phys.43(8), 085401 (2010).
[CrossRef]

J. Phys.- Condens. Mat. (1)

P. Dorenbos, “Thermal quenching of Eu2+ 5d-4f luminescence in inorganic compounds,” J. Phys.- Condens. Mat.17(50), 8103–8111 (2005).
[CrossRef]

J. Solid State Chem. (1)

Y. Q. Li, C. M. Fang, G. de With, and H. T. Hintzen, “Preparation, structure and photoluminescence properties of Eu2+ and Ce3+-doped SrYSi4N7,” J. Solid State Chem.177(12), 4687–4694 (2004).
[CrossRef]

J. Synchrotron Radiat. (2)

G. Derbyshire, K. C. Cheung, P. Sangsingkeow, and S. S. Hasnain, “A low-profile monolithic multi-element Ge detector for X-ray fluorescence applications,” J. Synchrotron Radiat.6(2), 62–63 (1999).
[CrossRef]

B. Ravel and M. Newville, “ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT,” J. Synchrotron Radiat.12(4), 537–541 (2005).
[CrossRef] [PubMed]

Mat. Sci. Eng. B-Solid (1)

K. T. Lethi, A. Garcia, F. Guillen, and C. Fouassier, “Investigation of the MS-Al2S3 systems (M = Ca, Sr, Ba) and luminescence properties of europium-doped thioaluminates,” Mat. Sci. Eng. B-Solid14, 393–397 (1992).
[CrossRef]

Mater. Res. Bull. (1)

Y. K. Kim, D. H. Cho, Y. K. Jeong, M. K. Nah, K. B. Kim, and J. G. Kang, “Luminescence characterization of (Ca1-xZnx)Ga2S4:Eu2+ phosphors for a white light-emitting diode,” Mater. Res. Bull.45(8), 905–909 (2010).
[CrossRef]

Materials (1)

R. J. Xie, N. Hirosaki, Y. Q. Li, and T. Takeda, “Rare-earth activated nitride phosphors: synthesis, luminescence and applications,” Materials3(6), 3777–3793 (2010).
[CrossRef]

Opt. Express (3)

Opt. Mater. (1)

J. J. Joos, K. W. Meert, A. B. Parmentier, D. Poelman, and P. F. Smet, “Thermal quenching and luminescence lifetime of saturated green Sr1-xEuxGa2S4 phosphors,” Opt. Mater.34(11), 1902–1907 (2012).
[CrossRef]

Opt. Mater. Express (2)

Phys. Chem. Chem. Phys. (1)

K. Korthout, A. B. Parmentier, P. F. Smet, and D. Poelman, “A XAS study of the luminescent Eu centers in thiosilicate phosphors,” Phys. Chem. Chem. Phys.15(22), 8678–8683 (2013).
[CrossRef] [PubMed]

Physica Status Solidi a-Applications and Materials Science (2)

R. J. Yu, H. K. Yang, B. K. Moon, B. C. Choi, and J. H. Jeong, “Luminescence properties of stoichiometric EuM2S4 (M = Ga, Al) conversion phosphors for white LED applications,” Physica Status Solidi a-Applications and Materials Science209(12), 2620–2625 (2012).
[CrossRef]

R. Mueller-Mach, G. Mueller, M. R. Krames, H. A. Hoppe, F. Stadler, W. Schnick, T. Juestel, and P. Schmidt, “Highly efficient all-nitride phosphor-converted white light emitting diode,” Physica Status Solidi a-Applications and Materials Science202(9), 1727–1732 (2005).
[CrossRef]

Z. Kristallogr. (1)

C. Wickleder, S. Zhang, and H. Haeuseler, “Photoluminescence of ZnGa2S4:Eu2+,” Z. Kristallogr.220(2-3-2005), 277–280 (2005).
[CrossRef]

Other (2)

V. K. Pecharsky and P. Y. Zavalij, Fundamentals of Powder Diffraction and Structural Characterization of Materials (Springer, 2005).

B. Henderson and G. F. Imbusch, Optical Spectroscopy of Inorganic Solids (Oxford University Press, Incorporated, 2006).

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (10)

Fig. 1
Fig. 1

Top: Diffuse reflectance spectra for ZnGa2S4 (x = 0.00), Zn0.99Eu0.01Ga2S4 (x = 0.01) and EuGa2S4 (x = 1.00) at room temperature. Bottom: PL emission (at 450 nm excitation, solid lines) and excitation (at 540 nm emission, dashed lines) spectra for Zn0.99Eu0.01Ga2S4 (x = 0.01) and EuGa2S4 (x = 1.00) at room temperature, normalized for better readability. The dip in the excitation spectra around 470 nm is an artifact.

Fig. 2
Fig. 2

Absorption (fraction of the incident photons that are absorbed), internal and external quantum efficiency for Zn1-xEuxGa2S4 at room temperature, measured at 460 nm excitation.

Fig. 3
Fig. 3

Normalized PL intensity and luminescent lifetimes as function of temperature for Zn0.94Eu0.06Ga2S4 upon excitation at 400 nm.

Fig. 4
Fig. 4

SEM-CL-EDX mapping of Zn0.99Eu0.01Ga2S4 powder, obtained at 250 K. Top left: phosphor morphology obtained by backscattered electron imaging. The integrated CL emission intensity is shown as an overlay in false colors. Top right: elemental distribution by EDX, where the colors are determined by color coding with green for Zn and red for Eu. Simultaneous detection would lead to a yellow color. Bottom: CL emission spectra for the points indicated in the top right figure, obtained in clockwise direction.

Fig. 5
Fig. 5

X-ray diffraction patterns for Zn1-xEuxGa2S4 powders, compared with reference patterns for ZnGa2S4 (ICSD 69542) and EuGa2S4 (ICSD 8053) [45, 47].

Fig. 6
Fig. 6

y(x), as defined in Eq. (2).

Fig. 7
Fig. 7

Eu LIII XANES spectrum of (top) Zn0.96Eu0.04Ga2S4, compared with the spectra of reference compounds for Eu2+ and Eu3+ (bottom), EuS (solid line) and Eu2O3 (dashed line).

Fig. 8
Fig. 8

Top: Zn K edge extracted EXAFS spectrum, Middle: Eu LIII edge extracted EXAFS spectrum, both in Zn0.96Eu0.04Ga2S, Bottom: Eu LIII edge extracted EXAFS spectrum in EuGa2S4.

Fig. 9
Fig. 9

Fourier transform of k 2 χ(k) to radial distance (r) space for a Zn0.92Eu0.08Ga2S4 powder (solid line) and the result of the simulation, based on the structure of EuGa2S4 and the europium ions occupying the octahedral voids (circles).

Fig. 10
Fig. 10

Left: Crystal structure of ZnGa2S4 where an Eu2+ dopant occupies an octahedral void (sixfold coordinated). The neighboring zinc ion is removed to compensate for the excess positive charge [45]. Right: Crystal structure of EuGa2S4, with (slightly distorted) square antiprismatic coordination polyhedra for Eu2+ (eightfold coordinated) [47].

Tables (2)

Tables Icon

Table 1 Overview of luminescent properties of green phosphors from recent literature. T0.5 describes the thermal quenching. It is the temperature at which the emission intensity is 50% of the value at low temperature. QE (int/ext) is the internal/external quantum efficiency.

Tables Icon

Table 2 Emission maxima (λmax) and full width at half maximum (FWHM), luminescent lifetimes (τ) and quenching temperatures (T0.5) of multiple Eu2+ doped thiogallate and thioaluminate phosphors. The displayed parameters were recorded at room temperature.

Equations (2)

Equations on this page are rendered with MathJax. Learn more.

η ext = N em N inc    η int = N em N abs    η ext =A η int
y(x)= I EuGa 2 S 4 I ZnGa 2 S 4 1x x

Metrics