Abstract

The variation of the optical properties of porous Vycor glass (Corning, Model 7930) under different relative-humidity conditions was studied. The adsorption of water into the glass pores was investigated with spectroscopic ellipsometry. The change of the refractive index was Δn ∼ 0.04 between 5% and 90% relative humidity. A linear relation between the ellipsometer parameter tan Ψ, the amount of water adsorbed in the glass pores, and information about the pore-size distributions was established. The results are in accord with the values obtained from N2 isotherms, transmission electron microscope micrographs, and the manufacturer’s specifications (radius of ∼20 Å). The possibility of using this material as a transducer for implementation in a fiber-optic sensor to measure humidity was evaluated.

© 2001 Optical Society of America

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References

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  1. A. Hohr, H. B. Neumann, P. W. Schmidt, P. Pfeifer, D. Avnir, “Fractal surface and cluster structure of controlled-pore glasses and Vycor porous glass as revealed by small-angle x-ray and neutron scattering,” Phys. Rev. B 38, 1462–1467 (1988).
    [CrossRef]
  2. M. J. Benhan, J. C. Cook, J. C. Li, D. K. Ross, “Small-angle neutron scattering study of adsorbed water in porous Vycor glass: supercooling phase transition and interfacial structure,” Phys. Rev. B 39, 633–636 (1989).
    [CrossRef]
  3. S. K. Das, R. Suryanarayanan, “Structural, optical, and electrical properties of Pb1-xYbxTe films (0 < x < 0.25),” J. Appl. Phys. 66, 4843–4845 (1989).
    [CrossRef]
  4. M. D. Dvorak, B. L. Justus, D. K. Gaskill, D. G. Hendersho, “Nonlinear absorption and refraction of quantum confined InP nanocrystals grown in porous glass,” Appl. Phys. Lett. 66, 804–806 (1995).
    [CrossRef]
  5. T. E. Huber, H. L. Tsou, “Temperature-dependent adsorption of nitrogen on porous Vycor glass,” Phys. Rev. B 57, 4991–4994 (1998).
    [CrossRef]
  6. T. E. Huber, C. A. Huber, “Adsorption of hydrogen on porous Vycor glass,” J. Low Temp. Phys. 80, 315–323 (1990).
    [CrossRef]
  7. B. Abeles, L. F. Chen, J. W. Johnson, J. M. Drake, “Capillary condensation and surface flow in microporous Vycor glass,” Isr. J. Chem. 31, 99–106 (1991).
    [CrossRef]
  8. Y. Hirama, T. Takahashi, M. Hino, T. Sato, “Studies of water adsorbed in porous Vycor glass,” J. Colloid Interface Sci. 184, 349–359 (1996).
    [CrossRef] [PubMed]
  9. P. Pissis, J. Laudat, D. Daoukaki, A. Kyritsis, “Dynamic properties of water in porous Vycor glass studied by dielectric techniques,” J. Non-Cryst. Solids 171, 201–207 (1994).
    [CrossRef]
  10. Special issue on the Second International Conference on Spectroscopic Ellipsometry, Thin Solid Films313–314 (1998).
  11. ES-4G User’s Manual (SOPRA SA., 26 rue Pierre Joigneaux, F92270 Bois-Colombes, France).
  12. ASAP 2010 Analyzer User’s Manual (Micromeritics, Norcross, Ga. 20093-1877).
  13. A. Alvarez-Herrero, A. J. Fort, H. Guerrero, E. Bernabeu, “Ellipsometric characterization and influence of relative humidity on TiO2 layers optical properties,” Thin Solid Films 349, 212–219 (1999).
    [CrossRef]
  14. S. Brunauer, L. S. Deming, W. S. Deming, E. Teller, “On a theory of the van der Waals adsorption of gases,” J. Am. Chem Soc. 62, 1723–1732 (1940).
    [CrossRef]
  15. S. Brunauer, P. H. Emmett, E. Teller, “Adsorption of gases in multimolecular layers,” J. Am. Chem. Soc. 60, 309–319 (1938).
    [CrossRef]
  16. S. J. Gregg, K. S. W. Sing, Adsorption, Surface Area, and Porosity (Academic, New York, 1997).
  17. H. G. Tompkins, A User’s Guide to Ellipsometry (Academic, New York, 1993).
  18. R. M. A. Azzam, N. N. Bashara, Ellipsometry and Polarized Light (North-Holland, Amsterdam, 1977).

1999 (1)

A. Alvarez-Herrero, A. J. Fort, H. Guerrero, E. Bernabeu, “Ellipsometric characterization and influence of relative humidity on TiO2 layers optical properties,” Thin Solid Films 349, 212–219 (1999).
[CrossRef]

1998 (2)

Special issue on the Second International Conference on Spectroscopic Ellipsometry, Thin Solid Films313–314 (1998).

T. E. Huber, H. L. Tsou, “Temperature-dependent adsorption of nitrogen on porous Vycor glass,” Phys. Rev. B 57, 4991–4994 (1998).
[CrossRef]

1996 (1)

Y. Hirama, T. Takahashi, M. Hino, T. Sato, “Studies of water adsorbed in porous Vycor glass,” J. Colloid Interface Sci. 184, 349–359 (1996).
[CrossRef] [PubMed]

1995 (1)

M. D. Dvorak, B. L. Justus, D. K. Gaskill, D. G. Hendersho, “Nonlinear absorption and refraction of quantum confined InP nanocrystals grown in porous glass,” Appl. Phys. Lett. 66, 804–806 (1995).
[CrossRef]

1994 (1)

P. Pissis, J. Laudat, D. Daoukaki, A. Kyritsis, “Dynamic properties of water in porous Vycor glass studied by dielectric techniques,” J. Non-Cryst. Solids 171, 201–207 (1994).
[CrossRef]

1991 (1)

B. Abeles, L. F. Chen, J. W. Johnson, J. M. Drake, “Capillary condensation and surface flow in microporous Vycor glass,” Isr. J. Chem. 31, 99–106 (1991).
[CrossRef]

1990 (1)

T. E. Huber, C. A. Huber, “Adsorption of hydrogen on porous Vycor glass,” J. Low Temp. Phys. 80, 315–323 (1990).
[CrossRef]

1989 (2)

M. J. Benhan, J. C. Cook, J. C. Li, D. K. Ross, “Small-angle neutron scattering study of adsorbed water in porous Vycor glass: supercooling phase transition and interfacial structure,” Phys. Rev. B 39, 633–636 (1989).
[CrossRef]

S. K. Das, R. Suryanarayanan, “Structural, optical, and electrical properties of Pb1-xYbxTe films (0 < x < 0.25),” J. Appl. Phys. 66, 4843–4845 (1989).
[CrossRef]

1988 (1)

A. Hohr, H. B. Neumann, P. W. Schmidt, P. Pfeifer, D. Avnir, “Fractal surface and cluster structure of controlled-pore glasses and Vycor porous glass as revealed by small-angle x-ray and neutron scattering,” Phys. Rev. B 38, 1462–1467 (1988).
[CrossRef]

1940 (1)

S. Brunauer, L. S. Deming, W. S. Deming, E. Teller, “On a theory of the van der Waals adsorption of gases,” J. Am. Chem Soc. 62, 1723–1732 (1940).
[CrossRef]

1938 (1)

S. Brunauer, P. H. Emmett, E. Teller, “Adsorption of gases in multimolecular layers,” J. Am. Chem. Soc. 60, 309–319 (1938).
[CrossRef]

Abeles, B.

B. Abeles, L. F. Chen, J. W. Johnson, J. M. Drake, “Capillary condensation and surface flow in microporous Vycor glass,” Isr. J. Chem. 31, 99–106 (1991).
[CrossRef]

Alvarez-Herrero, A.

A. Alvarez-Herrero, A. J. Fort, H. Guerrero, E. Bernabeu, “Ellipsometric characterization and influence of relative humidity on TiO2 layers optical properties,” Thin Solid Films 349, 212–219 (1999).
[CrossRef]

Avnir, D.

A. Hohr, H. B. Neumann, P. W. Schmidt, P. Pfeifer, D. Avnir, “Fractal surface and cluster structure of controlled-pore glasses and Vycor porous glass as revealed by small-angle x-ray and neutron scattering,” Phys. Rev. B 38, 1462–1467 (1988).
[CrossRef]

Azzam, R. M. A.

R. M. A. Azzam, N. N. Bashara, Ellipsometry and Polarized Light (North-Holland, Amsterdam, 1977).

Bashara, N. N.

R. M. A. Azzam, N. N. Bashara, Ellipsometry and Polarized Light (North-Holland, Amsterdam, 1977).

Benhan, M. J.

M. J. Benhan, J. C. Cook, J. C. Li, D. K. Ross, “Small-angle neutron scattering study of adsorbed water in porous Vycor glass: supercooling phase transition and interfacial structure,” Phys. Rev. B 39, 633–636 (1989).
[CrossRef]

Bernabeu, E.

A. Alvarez-Herrero, A. J. Fort, H. Guerrero, E. Bernabeu, “Ellipsometric characterization and influence of relative humidity on TiO2 layers optical properties,” Thin Solid Films 349, 212–219 (1999).
[CrossRef]

Brunauer, S.

S. Brunauer, L. S. Deming, W. S. Deming, E. Teller, “On a theory of the van der Waals adsorption of gases,” J. Am. Chem Soc. 62, 1723–1732 (1940).
[CrossRef]

S. Brunauer, P. H. Emmett, E. Teller, “Adsorption of gases in multimolecular layers,” J. Am. Chem. Soc. 60, 309–319 (1938).
[CrossRef]

Chen, L. F.

B. Abeles, L. F. Chen, J. W. Johnson, J. M. Drake, “Capillary condensation and surface flow in microporous Vycor glass,” Isr. J. Chem. 31, 99–106 (1991).
[CrossRef]

Cook, J. C.

M. J. Benhan, J. C. Cook, J. C. Li, D. K. Ross, “Small-angle neutron scattering study of adsorbed water in porous Vycor glass: supercooling phase transition and interfacial structure,” Phys. Rev. B 39, 633–636 (1989).
[CrossRef]

Daoukaki, D.

P. Pissis, J. Laudat, D. Daoukaki, A. Kyritsis, “Dynamic properties of water in porous Vycor glass studied by dielectric techniques,” J. Non-Cryst. Solids 171, 201–207 (1994).
[CrossRef]

Das, S. K.

S. K. Das, R. Suryanarayanan, “Structural, optical, and electrical properties of Pb1-xYbxTe films (0 < x < 0.25),” J. Appl. Phys. 66, 4843–4845 (1989).
[CrossRef]

Deming, L. S.

S. Brunauer, L. S. Deming, W. S. Deming, E. Teller, “On a theory of the van der Waals adsorption of gases,” J. Am. Chem Soc. 62, 1723–1732 (1940).
[CrossRef]

Deming, W. S.

S. Brunauer, L. S. Deming, W. S. Deming, E. Teller, “On a theory of the van der Waals adsorption of gases,” J. Am. Chem Soc. 62, 1723–1732 (1940).
[CrossRef]

Drake, J. M.

B. Abeles, L. F. Chen, J. W. Johnson, J. M. Drake, “Capillary condensation and surface flow in microporous Vycor glass,” Isr. J. Chem. 31, 99–106 (1991).
[CrossRef]

Dvorak, M. D.

M. D. Dvorak, B. L. Justus, D. K. Gaskill, D. G. Hendersho, “Nonlinear absorption and refraction of quantum confined InP nanocrystals grown in porous glass,” Appl. Phys. Lett. 66, 804–806 (1995).
[CrossRef]

Emmett, P. H.

S. Brunauer, P. H. Emmett, E. Teller, “Adsorption of gases in multimolecular layers,” J. Am. Chem. Soc. 60, 309–319 (1938).
[CrossRef]

Fort, A. J.

A. Alvarez-Herrero, A. J. Fort, H. Guerrero, E. Bernabeu, “Ellipsometric characterization and influence of relative humidity on TiO2 layers optical properties,” Thin Solid Films 349, 212–219 (1999).
[CrossRef]

Gaskill, D. K.

M. D. Dvorak, B. L. Justus, D. K. Gaskill, D. G. Hendersho, “Nonlinear absorption and refraction of quantum confined InP nanocrystals grown in porous glass,” Appl. Phys. Lett. 66, 804–806 (1995).
[CrossRef]

Gregg, S. J.

S. J. Gregg, K. S. W. Sing, Adsorption, Surface Area, and Porosity (Academic, New York, 1997).

Guerrero, H.

A. Alvarez-Herrero, A. J. Fort, H. Guerrero, E. Bernabeu, “Ellipsometric characterization and influence of relative humidity on TiO2 layers optical properties,” Thin Solid Films 349, 212–219 (1999).
[CrossRef]

Hendersho, D. G.

M. D. Dvorak, B. L. Justus, D. K. Gaskill, D. G. Hendersho, “Nonlinear absorption and refraction of quantum confined InP nanocrystals grown in porous glass,” Appl. Phys. Lett. 66, 804–806 (1995).
[CrossRef]

Hino, M.

Y. Hirama, T. Takahashi, M. Hino, T. Sato, “Studies of water adsorbed in porous Vycor glass,” J. Colloid Interface Sci. 184, 349–359 (1996).
[CrossRef] [PubMed]

Hirama, Y.

Y. Hirama, T. Takahashi, M. Hino, T. Sato, “Studies of water adsorbed in porous Vycor glass,” J. Colloid Interface Sci. 184, 349–359 (1996).
[CrossRef] [PubMed]

Hohr, A.

A. Hohr, H. B. Neumann, P. W. Schmidt, P. Pfeifer, D. Avnir, “Fractal surface and cluster structure of controlled-pore glasses and Vycor porous glass as revealed by small-angle x-ray and neutron scattering,” Phys. Rev. B 38, 1462–1467 (1988).
[CrossRef]

Huber, C. A.

T. E. Huber, C. A. Huber, “Adsorption of hydrogen on porous Vycor glass,” J. Low Temp. Phys. 80, 315–323 (1990).
[CrossRef]

Huber, T. E.

T. E. Huber, H. L. Tsou, “Temperature-dependent adsorption of nitrogen on porous Vycor glass,” Phys. Rev. B 57, 4991–4994 (1998).
[CrossRef]

T. E. Huber, C. A. Huber, “Adsorption of hydrogen on porous Vycor glass,” J. Low Temp. Phys. 80, 315–323 (1990).
[CrossRef]

Johnson, J. W.

B. Abeles, L. F. Chen, J. W. Johnson, J. M. Drake, “Capillary condensation and surface flow in microporous Vycor glass,” Isr. J. Chem. 31, 99–106 (1991).
[CrossRef]

Justus, B. L.

M. D. Dvorak, B. L. Justus, D. K. Gaskill, D. G. Hendersho, “Nonlinear absorption and refraction of quantum confined InP nanocrystals grown in porous glass,” Appl. Phys. Lett. 66, 804–806 (1995).
[CrossRef]

Kyritsis, A.

P. Pissis, J. Laudat, D. Daoukaki, A. Kyritsis, “Dynamic properties of water in porous Vycor glass studied by dielectric techniques,” J. Non-Cryst. Solids 171, 201–207 (1994).
[CrossRef]

Laudat, J.

P. Pissis, J. Laudat, D. Daoukaki, A. Kyritsis, “Dynamic properties of water in porous Vycor glass studied by dielectric techniques,” J. Non-Cryst. Solids 171, 201–207 (1994).
[CrossRef]

Li, J. C.

M. J. Benhan, J. C. Cook, J. C. Li, D. K. Ross, “Small-angle neutron scattering study of adsorbed water in porous Vycor glass: supercooling phase transition and interfacial structure,” Phys. Rev. B 39, 633–636 (1989).
[CrossRef]

Neumann, H. B.

A. Hohr, H. B. Neumann, P. W. Schmidt, P. Pfeifer, D. Avnir, “Fractal surface and cluster structure of controlled-pore glasses and Vycor porous glass as revealed by small-angle x-ray and neutron scattering,” Phys. Rev. B 38, 1462–1467 (1988).
[CrossRef]

Pfeifer, P.

A. Hohr, H. B. Neumann, P. W. Schmidt, P. Pfeifer, D. Avnir, “Fractal surface and cluster structure of controlled-pore glasses and Vycor porous glass as revealed by small-angle x-ray and neutron scattering,” Phys. Rev. B 38, 1462–1467 (1988).
[CrossRef]

Pissis, P.

P. Pissis, J. Laudat, D. Daoukaki, A. Kyritsis, “Dynamic properties of water in porous Vycor glass studied by dielectric techniques,” J. Non-Cryst. Solids 171, 201–207 (1994).
[CrossRef]

Ross, D. K.

M. J. Benhan, J. C. Cook, J. C. Li, D. K. Ross, “Small-angle neutron scattering study of adsorbed water in porous Vycor glass: supercooling phase transition and interfacial structure,” Phys. Rev. B 39, 633–636 (1989).
[CrossRef]

Sato, T.

Y. Hirama, T. Takahashi, M. Hino, T. Sato, “Studies of water adsorbed in porous Vycor glass,” J. Colloid Interface Sci. 184, 349–359 (1996).
[CrossRef] [PubMed]

Schmidt, P. W.

A. Hohr, H. B. Neumann, P. W. Schmidt, P. Pfeifer, D. Avnir, “Fractal surface and cluster structure of controlled-pore glasses and Vycor porous glass as revealed by small-angle x-ray and neutron scattering,” Phys. Rev. B 38, 1462–1467 (1988).
[CrossRef]

Sing, K. S. W.

S. J. Gregg, K. S. W. Sing, Adsorption, Surface Area, and Porosity (Academic, New York, 1997).

Suryanarayanan, R.

S. K. Das, R. Suryanarayanan, “Structural, optical, and electrical properties of Pb1-xYbxTe films (0 < x < 0.25),” J. Appl. Phys. 66, 4843–4845 (1989).
[CrossRef]

Takahashi, T.

Y. Hirama, T. Takahashi, M. Hino, T. Sato, “Studies of water adsorbed in porous Vycor glass,” J. Colloid Interface Sci. 184, 349–359 (1996).
[CrossRef] [PubMed]

Teller, E.

S. Brunauer, L. S. Deming, W. S. Deming, E. Teller, “On a theory of the van der Waals adsorption of gases,” J. Am. Chem Soc. 62, 1723–1732 (1940).
[CrossRef]

S. Brunauer, P. H. Emmett, E. Teller, “Adsorption of gases in multimolecular layers,” J. Am. Chem. Soc. 60, 309–319 (1938).
[CrossRef]

Tompkins, H. G.

H. G. Tompkins, A User’s Guide to Ellipsometry (Academic, New York, 1993).

Tsou, H. L.

T. E. Huber, H. L. Tsou, “Temperature-dependent adsorption of nitrogen on porous Vycor glass,” Phys. Rev. B 57, 4991–4994 (1998).
[CrossRef]

Appl. Phys. Lett. (1)

M. D. Dvorak, B. L. Justus, D. K. Gaskill, D. G. Hendersho, “Nonlinear absorption and refraction of quantum confined InP nanocrystals grown in porous glass,” Appl. Phys. Lett. 66, 804–806 (1995).
[CrossRef]

Isr. J. Chem. (1)

B. Abeles, L. F. Chen, J. W. Johnson, J. M. Drake, “Capillary condensation and surface flow in microporous Vycor glass,” Isr. J. Chem. 31, 99–106 (1991).
[CrossRef]

J. Am. Chem Soc. (1)

S. Brunauer, L. S. Deming, W. S. Deming, E. Teller, “On a theory of the van der Waals adsorption of gases,” J. Am. Chem Soc. 62, 1723–1732 (1940).
[CrossRef]

J. Am. Chem. Soc. (1)

S. Brunauer, P. H. Emmett, E. Teller, “Adsorption of gases in multimolecular layers,” J. Am. Chem. Soc. 60, 309–319 (1938).
[CrossRef]

J. Appl. Phys. (1)

S. K. Das, R. Suryanarayanan, “Structural, optical, and electrical properties of Pb1-xYbxTe films (0 < x < 0.25),” J. Appl. Phys. 66, 4843–4845 (1989).
[CrossRef]

J. Colloid Interface Sci. (1)

Y. Hirama, T. Takahashi, M. Hino, T. Sato, “Studies of water adsorbed in porous Vycor glass,” J. Colloid Interface Sci. 184, 349–359 (1996).
[CrossRef] [PubMed]

J. Low Temp. Phys. (1)

T. E. Huber, C. A. Huber, “Adsorption of hydrogen on porous Vycor glass,” J. Low Temp. Phys. 80, 315–323 (1990).
[CrossRef]

J. Non-Cryst. Solids (1)

P. Pissis, J. Laudat, D. Daoukaki, A. Kyritsis, “Dynamic properties of water in porous Vycor glass studied by dielectric techniques,” J. Non-Cryst. Solids 171, 201–207 (1994).
[CrossRef]

Phys. Rev. B (3)

T. E. Huber, H. L. Tsou, “Temperature-dependent adsorption of nitrogen on porous Vycor glass,” Phys. Rev. B 57, 4991–4994 (1998).
[CrossRef]

A. Hohr, H. B. Neumann, P. W. Schmidt, P. Pfeifer, D. Avnir, “Fractal surface and cluster structure of controlled-pore glasses and Vycor porous glass as revealed by small-angle x-ray and neutron scattering,” Phys. Rev. B 38, 1462–1467 (1988).
[CrossRef]

M. J. Benhan, J. C. Cook, J. C. Li, D. K. Ross, “Small-angle neutron scattering study of adsorbed water in porous Vycor glass: supercooling phase transition and interfacial structure,” Phys. Rev. B 39, 633–636 (1989).
[CrossRef]

Thin Solid Films (2)

Special issue on the Second International Conference on Spectroscopic Ellipsometry, Thin Solid Films313–314 (1998).

A. Alvarez-Herrero, A. J. Fort, H. Guerrero, E. Bernabeu, “Ellipsometric characterization and influence of relative humidity on TiO2 layers optical properties,” Thin Solid Films 349, 212–219 (1999).
[CrossRef]

Other (5)

S. J. Gregg, K. S. W. Sing, Adsorption, Surface Area, and Porosity (Academic, New York, 1997).

H. G. Tompkins, A User’s Guide to Ellipsometry (Academic, New York, 1993).

R. M. A. Azzam, N. N. Bashara, Ellipsometry and Polarized Light (North-Holland, Amsterdam, 1977).

ES-4G User’s Manual (SOPRA SA., 26 rue Pierre Joigneaux, F92270 Bois-Colombes, France).

ASAP 2010 Analyzer User’s Manual (Micromeritics, Norcross, Ga. 20093-1877).

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Figures (8)

Fig. 1
Fig. 1

Refractive index n of the Vycor sample measured at an incident angle of 55.09° for wavelengths from 400 to 835 nm with a RH of 32% and a temperature of 24 °C.

Fig. 2
Fig. 2

Change in the value of the refractive index n with the RH. The plots show values for a wavelength range of 400–835 nm. The reference was taken at a RH of 6.4%.

Fig. 3
Fig. 3

Adsorption (▲) and desorption (□) isotherms of ellipsometric measurements. The temperature inside the climatic chamber was 23.1 °C: (a) The value of tan Ψ versus the RH. The plot was smoothed (solid curve) to permit the calculation of the pore-size distribution shown in Fig. 5. (b) The value of the refractive index n plotted versus the RH.

Fig. 4
Fig. 4

Plot of tan Ψ versus the water volume fraction. Both the exact values and a linear approximation are shown. Note that the deviation between the plots is less than the repeatability of the ellipsometer (0.005).

Fig. 5
Fig. 5

Pore-size distribution calculated from the ellipsometric data [Fig. 3(a)].

Fig. 6
Fig. 6

Adsorption (▲) and desorption (□) isotherms of N2 for porous Vycor glass as measured with the Model ASAP 2010 analyzer.

Fig. 7
Fig. 7

Pore-size distribution calculated from the data of the N2 isotherms.

Fig. 8
Fig. 8

TEM micrograph of the Vycor sample.

Equations (7)

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

tan Ψ=tan Ψ0+ tan Ψnenef3Δf3.
tan Ψne, θ=-cos θne2-sin2 θ1/2-sin2 θcos θne2-sin2 θ1/2+sin2 θ,
 tan Ψne=2 sin2 θ cos θnene2-sin2 θ1/2cos θne2-sin2 θ1/2+sin2 θ2,
f1n12-ne2n12+2ne2+f2n22-ne2n22+2ne2+f3n32-ne2n32+2ne2=0,
a3x3+a2x2+a1x+a0=0,
a0=n12n22n32, a1=n12n222-3f3+n12n322-3f2+n22n322-3f1, a2=2n123f1-1+n223f2-1+n323f3-1, a3=-4.
nef3=3nen32-n222ne2+n12212ne4-2a2ne2-a1.

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