Abstract

Light pulses in the extreme ultraviolet (EUV) are generated in the photon energy range hν from 20 to 120 eV in the conversion media argon, neon, and helium by a tabletop high-repetition-rate 30-fs Ti:sapphire laser system. This high-harmonic radiation is applied in the energy range from 20 to 50 eV for photoelectron spectroscopy studies of clean and adsorbate covered Ni(111) and Pt(111) surfaces. The photoemission spectra of the clean Pt(111) surface show secondary electron emission structures that influence the cross-section analysis of CO-induced states. Taking these Pt resonances into consideration, the well-known 4σ and 5σ CO shape resonances are observed at photon energies of 37 and 28 eV. In contrast to previously published experimental data, a resonance is also observed at hν=31 eV for the CO 1π state. On the basis of theoretical approaches this signal structure is identified as an autoionization resonance, experimentally detected for the first time to our knowledge.

© 2003 Optical Society of America

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  29. D. A. Shirley, J. Stöhr, P. S. Wehner, R. S. Williams, and G. Apai, “Photoemission from noble metals and adsorbates using synchrotron radiation,” Phys. Scr. 16, 398–413 (1977).
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  30. D. E. Eastman and J. K. Cashion, “Photoemission energy-level measurements of chemisorbed CO and O on Ni,” Phys. Rev. Lett. 27, 1520–1523 (1971).
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  31. J. W. Davenport, “Ultraviolet photoionization cross sections for N2 and CO,” Phys. Rev. Lett. 36, 945–949 (1976).
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  32. D. M. Collins and W. E. Spicer, “The adsorption of CO, O2 and H2 on Pt. II. Ultraviolet photoelectron spectroscopy studies,” Surf. Sci. 69, 114–132 (1977).
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  33. D. Rieger, R. D. Schnell, and W. Steinmann, “Angular distribution patterns of photoelectrons from orbitals of CO adsorbed on Ni(100), Pt(111) and Pt(110),” Surf. Sci. 143, 157–176 (1984).
    [CrossRef]
  34. C. W. Seabury, T. N. Rhodin, M. M. Traum, R. Benbow, and Z. Hurych, “Angle-resolved polarization-dependent photoemission studies of carbon monoxide on iridium surfaces,” Surf. Sci. 97, 363–376 (1980).
    [CrossRef]
  35. P. Budau and G. Raseev, “Shape resonances in photoemission for CO molecules adsorbed on metallic surfaces: a model including backscattering,” Phys. Rev. B 51, 16993–17006 (1995).
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  36. M. Stener, P. Decleva, I. Cacelli, R. Moccia, and R. Montuoro, “Response function study of CO photoionization: ab initio SCF and density functional results,” Chem. Phys. 272, 15–25 (2001).
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    [CrossRef]
  38. V. Dose, J. Rogozik, A. M. Bradshaw, and K. C. Prince, “Inverse photoemission from CO coadsorbed with K on Pt(111),” Surf. Sci. 179, 90–100 (1987).
    [CrossRef]
  39. M. Stener and P. Decleva, “Time-dependent density functional calculations of molecular photoionization cross sections: N2 and PH3,” J. Chem. Phys. 112, 10871–10879 (2000).
    [CrossRef]
  40. S. K. Semenov, N. A. Cherepkov, G. H. Fecher and G. Schönhense, “Generalization of the atomic random-phase-approximation method for diatomic molecules: N2 photoionization cross-section calculations,” Phys. Rev. A 61, 032704 (2000).
    [CrossRef]

2001 (4)

P. Siffalovic, M. Drescher, M. Spieweck, T. Wiesenthal, Y. C. Lim, R. Weidner, A. Elizarov, and U. Heinzmann, “Laser-based apparatus for extended ultraviolet femtosecond time-resolved photoemission spectroscopy,” Rev. Sci. Instrum. 72, 30–35 (2001).
[CrossRef]

D. Riedel, J. L. Hernandez-Pozos, R. E. Palmer, S. Baggott, K. W. Kolasinski, and J. S. Foord, “Tunable pulsed vacuum ultraviolet light source for surface science and materials spectroscopy based on high order harmonic generation,” Rev. Sci. Instrum. 72, 1977–1983 (2001).
[CrossRef]

M. Bauer, C. Lei, K. Read, R. Tobey, J. Gland, M. M. Murnane, and H. C. Kapteyn, “Direct observation of surface chemistry using ultrafast soft-x-ray pulses,” Phys. Rev. Lett. 87, 025501 (2001).
[CrossRef]

M. Stener, P. Decleva, I. Cacelli, R. Moccia, and R. Montuoro, “Response function study of CO photoionization: ab initio SCF and density functional results,” Chem. Phys. 272, 15–25 (2001).
[CrossRef]

2000 (3)

L. Nugent-Glandorf, M. Scheer, M. Krishnamurthy, J. W. Odom, and S. R. Leone, “Photoelectron spectroscopic determination of the energy bandwidths of high-order harmonics (7th-55th) produced by an ultrafast laser in neon,” Phys. Rev. A 62, 023812 (2000).
[CrossRef]

M. Stener and P. Decleva, “Time-dependent density functional calculations of molecular photoionization cross sections: N2 and PH3,” J. Chem. Phys. 112, 10871–10879 (2000).
[CrossRef]

S. K. Semenov, N. A. Cherepkov, G. H. Fecher and G. Schönhense, “Generalization of the atomic random-phase-approximation method for diatomic molecules: N2 photoionization cross-section calculations,” Phys. Rev. A 61, 032704 (2000).
[CrossRef]

1999 (2)

M. N. Piancastelli, “The neverending story of shape resonances,” J. Electron Spectrosc. Relat. Phenom. 100, 167–190 (1999).
[CrossRef]

M. Schnürer, Z. Cheng, M. Hentschel, G. Tempea, P. Kalman, Th. Brabec, and F. Krausz, “Absorption-limited generation of coherent ultrashort soft x-ray pulses,” Phys. Rev. Lett. 83, 722–725 (1999).
[CrossRef]

1998 (1)

H. Aizawa and S. Tsuneyuki, “First-principle study of CO bonding to Pt(111): validity of the Blyholder model,” Surf. Sci. 399, L364–L370 (1998).
[CrossRef]

1997 (4)

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

K. L. Kostov, P. Jakob, and D. Menzel, “A new high density CO/oxygen coadsorbate layer on Pt(111) and its role in CO oxidation,” Surf. Sci. 377–379, 802–807 (1997).
[CrossRef]

Z. Chang, A. Rundquist, H. Wang, M. M. Murnane, and H. C. Kapteyn, “Generation of coherent soft x-rays at 2.7 nm using high harmonics,” Phys. Rev. Lett. 79, 2967–2970 (1997).
[CrossRef]

Ch. Spielmann, N. H. Burnett, S. Sartania, R. Koppitsch, M. Schnürer, C. Kan, M. Lenzner, P. Wobrauschek, and F. Krausz, “Generation of coherent x-rays in the water window using 5-femtosecond laser pulses,” Science 278, 661–664 (1997).
[CrossRef]

1995 (1)

P. Budau and G. Raseev, “Shape resonances in photoemission for CO molecules adsorbed on metallic surfaces: a model including backscattering,” Phys. Rev. B 51, 16993–17006 (1995).
[CrossRef]

1993 (3)

C.-G. Wahlström, J. Larsson, A. Persson, T. Starczewski, S. Svanberg, P. Salières, Ph. Balcou, and A. L’Huillier, “High-order harmonic generation in rare gases with an intense short-pulse laser,” Phys. Rev. A 48, 4709–4720 (1993).
[CrossRef] [PubMed]

A. L’Huillier and Ph. Balcou, “High-order harmonic generation in rare gases with a 1-ps 1053-nm laser,” Phys. Rev. Lett. 70, 774–777 (1993).
[CrossRef] [PubMed]

P. B. Corkum, “Plasma perspective on strong-field multiphoton ionization,” Phys. Rev. Lett. 71, 1994–1997 (1993).
[CrossRef] [PubMed]

1992 (1)

J. L. Krause, K. J. Schafer, and K. C. Kulander, “High-order harmonic generation from atoms and ions in the high intensity regime,” Phys. Rev. Lett. 68, 3535–3538 (1992).
[CrossRef] [PubMed]

1990 (1)

T. J. Gil, C. L. Winstedad, J. A. Sheehy, R. E. Farren, and P. W. Lanhoff, “New theoretical perspectives on molecular shape resonances: Feshbach–Fano methods for Mulliken orbital analysis of photoionization continua,” Phys. Scr. T31, 179–188 (1990).
[CrossRef]

1987 (1)

V. Dose, J. Rogozik, A. M. Bradshaw, and K. C. Prince, “Inverse photoemission from CO coadsorbed with K on Pt(111),” Surf. Sci. 179, 90–100 (1987).
[CrossRef]

1984 (1)

D. Rieger, R. D. Schnell, and W. Steinmann, “Angular distribution patterns of photoelectrons from orbitals of CO adsorbed on Ni(100), Pt(111) and Pt(110),” Surf. Sci. 143, 157–176 (1984).
[CrossRef]

1983 (1)

F. Greuter, D. Heskett, E. W. Plummer, and H.-J. Freund, “Chemisorption of CO on Co(0001). Structure and electronic properties,” Phys. Rev. B 27, 7117–7135 (1983).
[CrossRef]

1982 (2)

S. R. Bare, K. Griffiths, P. Hoffmann, D. A. King, G. L. Nyberg, N. V. Richardson, “A synchrotron radiation study of the electronic and geometric structure of CO on Pt{110},” Surf. Sci. 120, 367–375 (1982).
[CrossRef]

P. Hofmann, S. R. Bare, N. V. Richardson, and D. A. King, “Orientation of chemisorped species from orthogonal-plane ARUPS: tilted CO on Pt{110} and upright CO on Pt{111},” Solid State Commun. 42, 645–651 (1982).
[CrossRef]

1981 (1)

J. N. Miller, D. T. Ling, P. M. Stefan, D. L. Weissman, M. L. Shek, I. Lindau, and W. E. Spicer, “Synchrotron radiation studies of CO and H2O adsorbed on Pt,” Phys. Rev. B 24, 1917–1926 (1981).
[CrossRef]

1980 (1)

C. W. Seabury, T. N. Rhodin, M. M. Traum, R. Benbow, and Z. Hurych, “Angle-resolved polarization-dependent photoemission studies of carbon monoxide on iridium surfaces,” Surf. Sci. 97, 363–376 (1980).
[CrossRef]

1979 (1)

A. M. Bradshaw, “The structure and chemistry of adsorbed carbon monoxide,” Surf. Sci. 80, 215–225 (1979).
[CrossRef]

1977 (2)

D. M. Collins and W. E. Spicer, “The adsorption of CO, O2 and H2 on Pt. II. Ultraviolet photoelectron spectroscopy studies,” Surf. Sci. 69, 114–132 (1977).
[CrossRef]

D. A. Shirley, J. Stöhr, P. S. Wehner, R. S. Williams, and G. Apai, “Photoemission from noble metals and adsorbates using synchrotron radiation,” Phys. Scr. 16, 398–413 (1977).
[CrossRef]

1976 (3)

G. Apai, P. S. Wehner, R. S. Williams, J. Stöhr, and D. A. Shirley, “Orientation of CO on Pt(111) and Ni(111) surfaces from angle-resolved photoemission,” Phys. Rev. Lett. 37, 1497–1500 (1976).
[CrossRef]

H. Conrad, G. Ertl, J. Küppers, and E. E. Latta, “Adsorption of CO on clean and oxygen covered Ni(111),” Surf. Sci. 57, 475–484 (1976).
[CrossRef]

J. W. Davenport, “Ultraviolet photoionization cross sections for N2 and CO,” Phys. Rev. Lett. 36, 945–949 (1976).
[CrossRef]

1972 (1)

J. L. Dehmer, “Evidence of effective potential barriers in the x-ray absorption spectra of molecules,” J. Chem. Phys. 56, 4496–4504 (1972).
[CrossRef]

1971 (1)

D. E. Eastman and J. K. Cashion, “Photoemission energy-level measurements of chemisorbed CO and O on Ni,” Phys. Rev. Lett. 27, 1520–1523 (1971).
[CrossRef]

1964 (1)

G. Blyholder, “Molecular orbital view of chemisorbed carbon monoxide,” J. Phys. Chem. 68, 2772–2778 (1964).
[CrossRef]

Aizawa, H.

H. Aizawa and S. Tsuneyuki, “First-principle study of CO bonding to Pt(111): validity of the Blyholder model,” Surf. Sci. 399, L364–L370 (1998).
[CrossRef]

Apai, G.

D. A. Shirley, J. Stöhr, P. S. Wehner, R. S. Williams, and G. Apai, “Photoemission from noble metals and adsorbates using synchrotron radiation,” Phys. Scr. 16, 398–413 (1977).
[CrossRef]

G. Apai, P. S. Wehner, R. S. Williams, J. Stöhr, and D. A. Shirley, “Orientation of CO on Pt(111) and Ni(111) surfaces from angle-resolved photoemission,” Phys. Rev. Lett. 37, 1497–1500 (1976).
[CrossRef]

Baggott, S.

D. Riedel, J. L. Hernandez-Pozos, R. E. Palmer, S. Baggott, K. W. Kolasinski, and J. S. Foord, “Tunable pulsed vacuum ultraviolet light source for surface science and materials spectroscopy based on high order harmonic generation,” Rev. Sci. Instrum. 72, 1977–1983 (2001).
[CrossRef]

Balcou, Ph.

A. L’Huillier and Ph. Balcou, “High-order harmonic generation in rare gases with a 1-ps 1053-nm laser,” Phys. Rev. Lett. 70, 774–777 (1993).
[CrossRef] [PubMed]

C.-G. Wahlström, J. Larsson, A. Persson, T. Starczewski, S. Svanberg, P. Salières, Ph. Balcou, and A. L’Huillier, “High-order harmonic generation in rare gases with an intense short-pulse laser,” Phys. Rev. A 48, 4709–4720 (1993).
[CrossRef] [PubMed]

Bare, S. R.

P. Hofmann, S. R. Bare, N. V. Richardson, and D. A. King, “Orientation of chemisorped species from orthogonal-plane ARUPS: tilted CO on Pt{110} and upright CO on Pt{111},” Solid State Commun. 42, 645–651 (1982).
[CrossRef]

S. R. Bare, K. Griffiths, P. Hoffmann, D. A. King, G. L. Nyberg, N. V. Richardson, “A synchrotron radiation study of the electronic and geometric structure of CO on Pt{110},” Surf. Sci. 120, 367–375 (1982).
[CrossRef]

Bauer, M.

M. Bauer, C. Lei, K. Read, R. Tobey, J. Gland, M. M. Murnane, and H. C. Kapteyn, “Direct observation of surface chemistry using ultrafast soft-x-ray pulses,” Phys. Rev. Lett. 87, 025501 (2001).
[CrossRef]

Benbow, R.

C. W. Seabury, T. N. Rhodin, M. M. Traum, R. Benbow, and Z. Hurych, “Angle-resolved polarization-dependent photoemission studies of carbon monoxide on iridium surfaces,” Surf. Sci. 97, 363–376 (1980).
[CrossRef]

Bennich, P.

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

Blyholder, G.

G. Blyholder, “Molecular orbital view of chemisorbed carbon monoxide,” J. Phys. Chem. 68, 2772–2778 (1964).
[CrossRef]

Brabec, Th.

M. Schnürer, Z. Cheng, M. Hentschel, G. Tempea, P. Kalman, Th. Brabec, and F. Krausz, “Absorption-limited generation of coherent ultrashort soft x-ray pulses,” Phys. Rev. Lett. 83, 722–725 (1999).
[CrossRef]

Bradshaw, A. M.

V. Dose, J. Rogozik, A. M. Bradshaw, and K. C. Prince, “Inverse photoemission from CO coadsorbed with K on Pt(111),” Surf. Sci. 179, 90–100 (1987).
[CrossRef]

A. M. Bradshaw, “The structure and chemistry of adsorbed carbon monoxide,” Surf. Sci. 80, 215–225 (1979).
[CrossRef]

Budau, P.

P. Budau and G. Raseev, “Shape resonances in photoemission for CO molecules adsorbed on metallic surfaces: a model including backscattering,” Phys. Rev. B 51, 16993–17006 (1995).
[CrossRef]

Burnett, N. H.

Ch. Spielmann, N. H. Burnett, S. Sartania, R. Koppitsch, M. Schnürer, C. Kan, M. Lenzner, P. Wobrauschek, and F. Krausz, “Generation of coherent x-rays in the water window using 5-femtosecond laser pulses,” Science 278, 661–664 (1997).
[CrossRef]

Cacelli, I.

M. Stener, P. Decleva, I. Cacelli, R. Moccia, and R. Montuoro, “Response function study of CO photoionization: ab initio SCF and density functional results,” Chem. Phys. 272, 15–25 (2001).
[CrossRef]

Cashion, J. K.

D. E. Eastman and J. K. Cashion, “Photoemission energy-level measurements of chemisorbed CO and O on Ni,” Phys. Rev. Lett. 27, 1520–1523 (1971).
[CrossRef]

Chang, Z.

Z. Chang, A. Rundquist, H. Wang, M. M. Murnane, and H. C. Kapteyn, “Generation of coherent soft x-rays at 2.7 nm using high harmonics,” Phys. Rev. Lett. 79, 2967–2970 (1997).
[CrossRef]

Cheng, Z.

M. Schnürer, Z. Cheng, M. Hentschel, G. Tempea, P. Kalman, Th. Brabec, and F. Krausz, “Absorption-limited generation of coherent ultrashort soft x-ray pulses,” Phys. Rev. Lett. 83, 722–725 (1999).
[CrossRef]

Cherepkov, N. A.

S. K. Semenov, N. A. Cherepkov, G. H. Fecher and G. Schönhense, “Generalization of the atomic random-phase-approximation method for diatomic molecules: N2 photoionization cross-section calculations,” Phys. Rev. A 61, 032704 (2000).
[CrossRef]

Collins, D. M.

D. M. Collins and W. E. Spicer, “The adsorption of CO, O2 and H2 on Pt. II. Ultraviolet photoelectron spectroscopy studies,” Surf. Sci. 69, 114–132 (1977).
[CrossRef]

Conrad, H.

H. Conrad, G. Ertl, J. Küppers, and E. E. Latta, “Adsorption of CO on clean and oxygen covered Ni(111),” Surf. Sci. 57, 475–484 (1976).
[CrossRef]

Corkum, P. B.

P. B. Corkum, “Plasma perspective on strong-field multiphoton ionization,” Phys. Rev. Lett. 71, 1994–1997 (1993).
[CrossRef] [PubMed]

Davenport, J. W.

J. W. Davenport, “Ultraviolet photoionization cross sections for N2 and CO,” Phys. Rev. Lett. 36, 945–949 (1976).
[CrossRef]

Decleva, P.

M. Stener, P. Decleva, I. Cacelli, R. Moccia, and R. Montuoro, “Response function study of CO photoionization: ab initio SCF and density functional results,” Chem. Phys. 272, 15–25 (2001).
[CrossRef]

M. Stener and P. Decleva, “Time-dependent density functional calculations of molecular photoionization cross sections: N2 and PH3,” J. Chem. Phys. 112, 10871–10879 (2000).
[CrossRef]

Dehmer, J. L.

J. L. Dehmer, “Evidence of effective potential barriers in the x-ray absorption spectra of molecules,” J. Chem. Phys. 56, 4496–4504 (1972).
[CrossRef]

Dose, V.

V. Dose, J. Rogozik, A. M. Bradshaw, and K. C. Prince, “Inverse photoemission from CO coadsorbed with K on Pt(111),” Surf. Sci. 179, 90–100 (1987).
[CrossRef]

Drescher, M.

P. Siffalovic, M. Drescher, M. Spieweck, T. Wiesenthal, Y. C. Lim, R. Weidner, A. Elizarov, and U. Heinzmann, “Laser-based apparatus for extended ultraviolet femtosecond time-resolved photoemission spectroscopy,” Rev. Sci. Instrum. 72, 30–35 (2001).
[CrossRef]

Eastman, D. E.

D. E. Eastman and J. K. Cashion, “Photoemission energy-level measurements of chemisorbed CO and O on Ni,” Phys. Rev. Lett. 27, 1520–1523 (1971).
[CrossRef]

Elizarov, A.

P. Siffalovic, M. Drescher, M. Spieweck, T. Wiesenthal, Y. C. Lim, R. Weidner, A. Elizarov, and U. Heinzmann, “Laser-based apparatus for extended ultraviolet femtosecond time-resolved photoemission spectroscopy,” Rev. Sci. Instrum. 72, 30–35 (2001).
[CrossRef]

Ertl, G.

H. Conrad, G. Ertl, J. Küppers, and E. E. Latta, “Adsorption of CO on clean and oxygen covered Ni(111),” Surf. Sci. 57, 475–484 (1976).
[CrossRef]

Farren, R. E.

T. J. Gil, C. L. Winstedad, J. A. Sheehy, R. E. Farren, and P. W. Lanhoff, “New theoretical perspectives on molecular shape resonances: Feshbach–Fano methods for Mulliken orbital analysis of photoionization continua,” Phys. Scr. T31, 179–188 (1990).
[CrossRef]

Fecher, G. H.

S. K. Semenov, N. A. Cherepkov, G. H. Fecher and G. Schönhense, “Generalization of the atomic random-phase-approximation method for diatomic molecules: N2 photoionization cross-section calculations,” Phys. Rev. A 61, 032704 (2000).
[CrossRef]

Föhlisch, A.

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

Foord, J. S.

D. Riedel, J. L. Hernandez-Pozos, R. E. Palmer, S. Baggott, K. W. Kolasinski, and J. S. Foord, “Tunable pulsed vacuum ultraviolet light source for surface science and materials spectroscopy based on high order harmonic generation,” Rev. Sci. Instrum. 72, 1977–1983 (2001).
[CrossRef]

Freund, H.-J.

F. Greuter, D. Heskett, E. W. Plummer, and H.-J. Freund, “Chemisorption of CO on Co(0001). Structure and electronic properties,” Phys. Rev. B 27, 7117–7135 (1983).
[CrossRef]

Gil, T. J.

T. J. Gil, C. L. Winstedad, J. A. Sheehy, R. E. Farren, and P. W. Lanhoff, “New theoretical perspectives on molecular shape resonances: Feshbach–Fano methods for Mulliken orbital analysis of photoionization continua,” Phys. Scr. T31, 179–188 (1990).
[CrossRef]

Gland, J.

M. Bauer, C. Lei, K. Read, R. Tobey, J. Gland, M. M. Murnane, and H. C. Kapteyn, “Direct observation of surface chemistry using ultrafast soft-x-ray pulses,” Phys. Rev. Lett. 87, 025501 (2001).
[CrossRef]

Greuter, F.

F. Greuter, D. Heskett, E. W. Plummer, and H.-J. Freund, “Chemisorption of CO on Co(0001). Structure and electronic properties,” Phys. Rev. B 27, 7117–7135 (1983).
[CrossRef]

Griffiths, K.

S. R. Bare, K. Griffiths, P. Hoffmann, D. A. King, G. L. Nyberg, N. V. Richardson, “A synchrotron radiation study of the electronic and geometric structure of CO on Pt{110},” Surf. Sci. 120, 367–375 (1982).
[CrossRef]

Hasselström, J.

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

Heinzmann, U.

P. Siffalovic, M. Drescher, M. Spieweck, T. Wiesenthal, Y. C. Lim, R. Weidner, A. Elizarov, and U. Heinzmann, “Laser-based apparatus for extended ultraviolet femtosecond time-resolved photoemission spectroscopy,” Rev. Sci. Instrum. 72, 30–35 (2001).
[CrossRef]

Hentschel, M.

M. Schnürer, Z. Cheng, M. Hentschel, G. Tempea, P. Kalman, Th. Brabec, and F. Krausz, “Absorption-limited generation of coherent ultrashort soft x-ray pulses,” Phys. Rev. Lett. 83, 722–725 (1999).
[CrossRef]

Hernandez-Pozos, J. L.

D. Riedel, J. L. Hernandez-Pozos, R. E. Palmer, S. Baggott, K. W. Kolasinski, and J. S. Foord, “Tunable pulsed vacuum ultraviolet light source for surface science and materials spectroscopy based on high order harmonic generation,” Rev. Sci. Instrum. 72, 1977–1983 (2001).
[CrossRef]

Heskett, D.

F. Greuter, D. Heskett, E. W. Plummer, and H.-J. Freund, “Chemisorption of CO on Co(0001). Structure and electronic properties,” Phys. Rev. B 27, 7117–7135 (1983).
[CrossRef]

Hoffmann, P.

S. R. Bare, K. Griffiths, P. Hoffmann, D. A. King, G. L. Nyberg, N. V. Richardson, “A synchrotron radiation study of the electronic and geometric structure of CO on Pt{110},” Surf. Sci. 120, 367–375 (1982).
[CrossRef]

Hofmann, P.

P. Hofmann, S. R. Bare, N. V. Richardson, and D. A. King, “Orientation of chemisorped species from orthogonal-plane ARUPS: tilted CO on Pt{110} and upright CO on Pt{111},” Solid State Commun. 42, 645–651 (1982).
[CrossRef]

Hurych, Z.

C. W. Seabury, T. N. Rhodin, M. M. Traum, R. Benbow, and Z. Hurych, “Angle-resolved polarization-dependent photoemission studies of carbon monoxide on iridium surfaces,” Surf. Sci. 97, 363–376 (1980).
[CrossRef]

Jakob, P.

K. L. Kostov, P. Jakob, and D. Menzel, “A new high density CO/oxygen coadsorbate layer on Pt(111) and its role in CO oxidation,” Surf. Sci. 377–379, 802–807 (1997).
[CrossRef]

Kalman, P.

M. Schnürer, Z. Cheng, M. Hentschel, G. Tempea, P. Kalman, Th. Brabec, and F. Krausz, “Absorption-limited generation of coherent ultrashort soft x-ray pulses,” Phys. Rev. Lett. 83, 722–725 (1999).
[CrossRef]

Kan, C.

Ch. Spielmann, N. H. Burnett, S. Sartania, R. Koppitsch, M. Schnürer, C. Kan, M. Lenzner, P. Wobrauschek, and F. Krausz, “Generation of coherent x-rays in the water window using 5-femtosecond laser pulses,” Science 278, 661–664 (1997).
[CrossRef]

Kapteyn, H. C.

M. Bauer, C. Lei, K. Read, R. Tobey, J. Gland, M. M. Murnane, and H. C. Kapteyn, “Direct observation of surface chemistry using ultrafast soft-x-ray pulses,” Phys. Rev. Lett. 87, 025501 (2001).
[CrossRef]

Z. Chang, A. Rundquist, H. Wang, M. M. Murnane, and H. C. Kapteyn, “Generation of coherent soft x-rays at 2.7 nm using high harmonics,” Phys. Rev. Lett. 79, 2967–2970 (1997).
[CrossRef]

Karis, O.

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

King, D. A.

S. R. Bare, K. Griffiths, P. Hoffmann, D. A. King, G. L. Nyberg, N. V. Richardson, “A synchrotron radiation study of the electronic and geometric structure of CO on Pt{110},” Surf. Sci. 120, 367–375 (1982).
[CrossRef]

P. Hofmann, S. R. Bare, N. V. Richardson, and D. A. King, “Orientation of chemisorped species from orthogonal-plane ARUPS: tilted CO on Pt{110} and upright CO on Pt{111},” Solid State Commun. 42, 645–651 (1982).
[CrossRef]

Kolasinski, K. W.

D. Riedel, J. L. Hernandez-Pozos, R. E. Palmer, S. Baggott, K. W. Kolasinski, and J. S. Foord, “Tunable pulsed vacuum ultraviolet light source for surface science and materials spectroscopy based on high order harmonic generation,” Rev. Sci. Instrum. 72, 1977–1983 (2001).
[CrossRef]

Koppitsch, R.

Ch. Spielmann, N. H. Burnett, S. Sartania, R. Koppitsch, M. Schnürer, C. Kan, M. Lenzner, P. Wobrauschek, and F. Krausz, “Generation of coherent x-rays in the water window using 5-femtosecond laser pulses,” Science 278, 661–664 (1997).
[CrossRef]

Kostov, K. L.

K. L. Kostov, P. Jakob, and D. Menzel, “A new high density CO/oxygen coadsorbate layer on Pt(111) and its role in CO oxidation,” Surf. Sci. 377–379, 802–807 (1997).
[CrossRef]

Krause, J. L.

J. L. Krause, K. J. Schafer, and K. C. Kulander, “High-order harmonic generation from atoms and ions in the high intensity regime,” Phys. Rev. Lett. 68, 3535–3538 (1992).
[CrossRef] [PubMed]

Krausz, F.

M. Schnürer, Z. Cheng, M. Hentschel, G. Tempea, P. Kalman, Th. Brabec, and F. Krausz, “Absorption-limited generation of coherent ultrashort soft x-ray pulses,” Phys. Rev. Lett. 83, 722–725 (1999).
[CrossRef]

Ch. Spielmann, N. H. Burnett, S. Sartania, R. Koppitsch, M. Schnürer, C. Kan, M. Lenzner, P. Wobrauschek, and F. Krausz, “Generation of coherent x-rays in the water window using 5-femtosecond laser pulses,” Science 278, 661–664 (1997).
[CrossRef]

Krishnamurthy, M.

L. Nugent-Glandorf, M. Scheer, M. Krishnamurthy, J. W. Odom, and S. R. Leone, “Photoelectron spectroscopic determination of the energy bandwidths of high-order harmonics (7th-55th) produced by an ultrafast laser in neon,” Phys. Rev. A 62, 023812 (2000).
[CrossRef]

Kulander, K. C.

J. L. Krause, K. J. Schafer, and K. C. Kulander, “High-order harmonic generation from atoms and ions in the high intensity regime,” Phys. Rev. Lett. 68, 3535–3538 (1992).
[CrossRef] [PubMed]

Küppers, J.

H. Conrad, G. Ertl, J. Küppers, and E. E. Latta, “Adsorption of CO on clean and oxygen covered Ni(111),” Surf. Sci. 57, 475–484 (1976).
[CrossRef]

L’Huillier, A.

A. L’Huillier and Ph. Balcou, “High-order harmonic generation in rare gases with a 1-ps 1053-nm laser,” Phys. Rev. Lett. 70, 774–777 (1993).
[CrossRef] [PubMed]

C.-G. Wahlström, J. Larsson, A. Persson, T. Starczewski, S. Svanberg, P. Salières, Ph. Balcou, and A. L’Huillier, “High-order harmonic generation in rare gases with an intense short-pulse laser,” Phys. Rev. A 48, 4709–4720 (1993).
[CrossRef] [PubMed]

Lanhoff, P. W.

T. J. Gil, C. L. Winstedad, J. A. Sheehy, R. E. Farren, and P. W. Lanhoff, “New theoretical perspectives on molecular shape resonances: Feshbach–Fano methods for Mulliken orbital analysis of photoionization continua,” Phys. Scr. T31, 179–188 (1990).
[CrossRef]

Larsson, J.

C.-G. Wahlström, J. Larsson, A. Persson, T. Starczewski, S. Svanberg, P. Salières, Ph. Balcou, and A. L’Huillier, “High-order harmonic generation in rare gases with an intense short-pulse laser,” Phys. Rev. A 48, 4709–4720 (1993).
[CrossRef] [PubMed]

Latta, E. E.

H. Conrad, G. Ertl, J. Küppers, and E. E. Latta, “Adsorption of CO on clean and oxygen covered Ni(111),” Surf. Sci. 57, 475–484 (1976).
[CrossRef]

Lei, C.

M. Bauer, C. Lei, K. Read, R. Tobey, J. Gland, M. M. Murnane, and H. C. Kapteyn, “Direct observation of surface chemistry using ultrafast soft-x-ray pulses,” Phys. Rev. Lett. 87, 025501 (2001).
[CrossRef]

Lenzner, M.

Ch. Spielmann, N. H. Burnett, S. Sartania, R. Koppitsch, M. Schnürer, C. Kan, M. Lenzner, P. Wobrauschek, and F. Krausz, “Generation of coherent x-rays in the water window using 5-femtosecond laser pulses,” Science 278, 661–664 (1997).
[CrossRef]

Leone, S. R.

L. Nugent-Glandorf, M. Scheer, M. Krishnamurthy, J. W. Odom, and S. R. Leone, “Photoelectron spectroscopic determination of the energy bandwidths of high-order harmonics (7th-55th) produced by an ultrafast laser in neon,” Phys. Rev. A 62, 023812 (2000).
[CrossRef]

Lim, Y. C.

P. Siffalovic, M. Drescher, M. Spieweck, T. Wiesenthal, Y. C. Lim, R. Weidner, A. Elizarov, and U. Heinzmann, “Laser-based apparatus for extended ultraviolet femtosecond time-resolved photoemission spectroscopy,” Rev. Sci. Instrum. 72, 30–35 (2001).
[CrossRef]

Lindau, I.

J. N. Miller, D. T. Ling, P. M. Stefan, D. L. Weissman, M. L. Shek, I. Lindau, and W. E. Spicer, “Synchrotron radiation studies of CO and H2O adsorbed on Pt,” Phys. Rev. B 24, 1917–1926 (1981).
[CrossRef]

Ling, D. T.

J. N. Miller, D. T. Ling, P. M. Stefan, D. L. Weissman, M. L. Shek, I. Lindau, and W. E. Spicer, “Synchrotron radiation studies of CO and H2O adsorbed on Pt,” Phys. Rev. B 24, 1917–1926 (1981).
[CrossRef]

Menzel, D.

K. L. Kostov, P. Jakob, and D. Menzel, “A new high density CO/oxygen coadsorbate layer on Pt(111) and its role in CO oxidation,” Surf. Sci. 377–379, 802–807 (1997).
[CrossRef]

Miller, J. N.

J. N. Miller, D. T. Ling, P. M. Stefan, D. L. Weissman, M. L. Shek, I. Lindau, and W. E. Spicer, “Synchrotron radiation studies of CO and H2O adsorbed on Pt,” Phys. Rev. B 24, 1917–1926 (1981).
[CrossRef]

Moccia, R.

M. Stener, P. Decleva, I. Cacelli, R. Moccia, and R. Montuoro, “Response function study of CO photoionization: ab initio SCF and density functional results,” Chem. Phys. 272, 15–25 (2001).
[CrossRef]

Montuoro, R.

M. Stener, P. Decleva, I. Cacelli, R. Moccia, and R. Montuoro, “Response function study of CO photoionization: ab initio SCF and density functional results,” Chem. Phys. 272, 15–25 (2001).
[CrossRef]

Murnane, M. M.

M. Bauer, C. Lei, K. Read, R. Tobey, J. Gland, M. M. Murnane, and H. C. Kapteyn, “Direct observation of surface chemistry using ultrafast soft-x-ray pulses,” Phys. Rev. Lett. 87, 025501 (2001).
[CrossRef]

Z. Chang, A. Rundquist, H. Wang, M. M. Murnane, and H. C. Kapteyn, “Generation of coherent soft x-rays at 2.7 nm using high harmonics,” Phys. Rev. Lett. 79, 2967–2970 (1997).
[CrossRef]

Nilsson, A.

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

Nugent-Glandorf, L.

L. Nugent-Glandorf, M. Scheer, M. Krishnamurthy, J. W. Odom, and S. R. Leone, “Photoelectron spectroscopic determination of the energy bandwidths of high-order harmonics (7th-55th) produced by an ultrafast laser in neon,” Phys. Rev. A 62, 023812 (2000).
[CrossRef]

Nyberg, G. L.

S. R. Bare, K. Griffiths, P. Hoffmann, D. A. King, G. L. Nyberg, N. V. Richardson, “A synchrotron radiation study of the electronic and geometric structure of CO on Pt{110},” Surf. Sci. 120, 367–375 (1982).
[CrossRef]

Odom, J. W.

L. Nugent-Glandorf, M. Scheer, M. Krishnamurthy, J. W. Odom, and S. R. Leone, “Photoelectron spectroscopic determination of the energy bandwidths of high-order harmonics (7th-55th) produced by an ultrafast laser in neon,” Phys. Rev. A 62, 023812 (2000).
[CrossRef]

Palmer, R. E.

D. Riedel, J. L. Hernandez-Pozos, R. E. Palmer, S. Baggott, K. W. Kolasinski, and J. S. Foord, “Tunable pulsed vacuum ultraviolet light source for surface science and materials spectroscopy based on high order harmonic generation,” Rev. Sci. Instrum. 72, 1977–1983 (2001).
[CrossRef]

Persson, A.

C.-G. Wahlström, J. Larsson, A. Persson, T. Starczewski, S. Svanberg, P. Salières, Ph. Balcou, and A. L’Huillier, “High-order harmonic generation in rare gases with an intense short-pulse laser,” Phys. Rev. A 48, 4709–4720 (1993).
[CrossRef] [PubMed]

Piancastelli, M. N.

M. N. Piancastelli, “The neverending story of shape resonances,” J. Electron Spectrosc. Relat. Phenom. 100, 167–190 (1999).
[CrossRef]

Plummer, E. W.

F. Greuter, D. Heskett, E. W. Plummer, and H.-J. Freund, “Chemisorption of CO on Co(0001). Structure and electronic properties,” Phys. Rev. B 27, 7117–7135 (1983).
[CrossRef]

Prince, K. C.

V. Dose, J. Rogozik, A. M. Bradshaw, and K. C. Prince, “Inverse photoemission from CO coadsorbed with K on Pt(111),” Surf. Sci. 179, 90–100 (1987).
[CrossRef]

Raseev, G.

P. Budau and G. Raseev, “Shape resonances in photoemission for CO molecules adsorbed on metallic surfaces: a model including backscattering,” Phys. Rev. B 51, 16993–17006 (1995).
[CrossRef]

Read, K.

M. Bauer, C. Lei, K. Read, R. Tobey, J. Gland, M. M. Murnane, and H. C. Kapteyn, “Direct observation of surface chemistry using ultrafast soft-x-ray pulses,” Phys. Rev. Lett. 87, 025501 (2001).
[CrossRef]

Rhodin, T. N.

C. W. Seabury, T. N. Rhodin, M. M. Traum, R. Benbow, and Z. Hurych, “Angle-resolved polarization-dependent photoemission studies of carbon monoxide on iridium surfaces,” Surf. Sci. 97, 363–376 (1980).
[CrossRef]

Richardson, N. V.

S. R. Bare, K. Griffiths, P. Hoffmann, D. A. King, G. L. Nyberg, N. V. Richardson, “A synchrotron radiation study of the electronic and geometric structure of CO on Pt{110},” Surf. Sci. 120, 367–375 (1982).
[CrossRef]

P. Hofmann, S. R. Bare, N. V. Richardson, and D. A. King, “Orientation of chemisorped species from orthogonal-plane ARUPS: tilted CO on Pt{110} and upright CO on Pt{111},” Solid State Commun. 42, 645–651 (1982).
[CrossRef]

Riedel, D.

D. Riedel, J. L. Hernandez-Pozos, R. E. Palmer, S. Baggott, K. W. Kolasinski, and J. S. Foord, “Tunable pulsed vacuum ultraviolet light source for surface science and materials spectroscopy based on high order harmonic generation,” Rev. Sci. Instrum. 72, 1977–1983 (2001).
[CrossRef]

Rieger, D.

D. Rieger, R. D. Schnell, and W. Steinmann, “Angular distribution patterns of photoelectrons from orbitals of CO adsorbed on Ni(100), Pt(111) and Pt(110),” Surf. Sci. 143, 157–176 (1984).
[CrossRef]

Rogozik, J.

V. Dose, J. Rogozik, A. M. Bradshaw, and K. C. Prince, “Inverse photoemission from CO coadsorbed with K on Pt(111),” Surf. Sci. 179, 90–100 (1987).
[CrossRef]

Rundquist, A.

Z. Chang, A. Rundquist, H. Wang, M. M. Murnane, and H. C. Kapteyn, “Generation of coherent soft x-rays at 2.7 nm using high harmonics,” Phys. Rev. Lett. 79, 2967–2970 (1997).
[CrossRef]

Salières, P.

C.-G. Wahlström, J. Larsson, A. Persson, T. Starczewski, S. Svanberg, P. Salières, Ph. Balcou, and A. L’Huillier, “High-order harmonic generation in rare gases with an intense short-pulse laser,” Phys. Rev. A 48, 4709–4720 (1993).
[CrossRef] [PubMed]

Samant, M.

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

Sartania, S.

Ch. Spielmann, N. H. Burnett, S. Sartania, R. Koppitsch, M. Schnürer, C. Kan, M. Lenzner, P. Wobrauschek, and F. Krausz, “Generation of coherent x-rays in the water window using 5-femtosecond laser pulses,” Science 278, 661–664 (1997).
[CrossRef]

Schafer, K. J.

J. L. Krause, K. J. Schafer, and K. C. Kulander, “High-order harmonic generation from atoms and ions in the high intensity regime,” Phys. Rev. Lett. 68, 3535–3538 (1992).
[CrossRef] [PubMed]

Scheer, M.

L. Nugent-Glandorf, M. Scheer, M. Krishnamurthy, J. W. Odom, and S. R. Leone, “Photoelectron spectroscopic determination of the energy bandwidths of high-order harmonics (7th-55th) produced by an ultrafast laser in neon,” Phys. Rev. A 62, 023812 (2000).
[CrossRef]

Schnell, R. D.

D. Rieger, R. D. Schnell, and W. Steinmann, “Angular distribution patterns of photoelectrons from orbitals of CO adsorbed on Ni(100), Pt(111) and Pt(110),” Surf. Sci. 143, 157–176 (1984).
[CrossRef]

Schnürer, M.

M. Schnürer, Z. Cheng, M. Hentschel, G. Tempea, P. Kalman, Th. Brabec, and F. Krausz, “Absorption-limited generation of coherent ultrashort soft x-ray pulses,” Phys. Rev. Lett. 83, 722–725 (1999).
[CrossRef]

Ch. Spielmann, N. H. Burnett, S. Sartania, R. Koppitsch, M. Schnürer, C. Kan, M. Lenzner, P. Wobrauschek, and F. Krausz, “Generation of coherent x-rays in the water window using 5-femtosecond laser pulses,” Science 278, 661–664 (1997).
[CrossRef]

Schönhense, G.

S. K. Semenov, N. A. Cherepkov, G. H. Fecher and G. Schönhense, “Generalization of the atomic random-phase-approximation method for diatomic molecules: N2 photoionization cross-section calculations,” Phys. Rev. A 61, 032704 (2000).
[CrossRef]

Seabury, C. W.

C. W. Seabury, T. N. Rhodin, M. M. Traum, R. Benbow, and Z. Hurych, “Angle-resolved polarization-dependent photoemission studies of carbon monoxide on iridium surfaces,” Surf. Sci. 97, 363–376 (1980).
[CrossRef]

Semenov, S. K.

S. K. Semenov, N. A. Cherepkov, G. H. Fecher and G. Schönhense, “Generalization of the atomic random-phase-approximation method for diatomic molecules: N2 photoionization cross-section calculations,” Phys. Rev. A 61, 032704 (2000).
[CrossRef]

Sheehy, J. A.

T. J. Gil, C. L. Winstedad, J. A. Sheehy, R. E. Farren, and P. W. Lanhoff, “New theoretical perspectives on molecular shape resonances: Feshbach–Fano methods for Mulliken orbital analysis of photoionization continua,” Phys. Scr. T31, 179–188 (1990).
[CrossRef]

Shek, M. L.

J. N. Miller, D. T. Ling, P. M. Stefan, D. L. Weissman, M. L. Shek, I. Lindau, and W. E. Spicer, “Synchrotron radiation studies of CO and H2O adsorbed on Pt,” Phys. Rev. B 24, 1917–1926 (1981).
[CrossRef]

Shirley, D. A.

D. A. Shirley, J. Stöhr, P. S. Wehner, R. S. Williams, and G. Apai, “Photoemission from noble metals and adsorbates using synchrotron radiation,” Phys. Scr. 16, 398–413 (1977).
[CrossRef]

G. Apai, P. S. Wehner, R. S. Williams, J. Stöhr, and D. A. Shirley, “Orientation of CO on Pt(111) and Ni(111) surfaces from angle-resolved photoemission,” Phys. Rev. Lett. 37, 1497–1500 (1976).
[CrossRef]

Siffalovic, P.

P. Siffalovic, M. Drescher, M. Spieweck, T. Wiesenthal, Y. C. Lim, R. Weidner, A. Elizarov, and U. Heinzmann, “Laser-based apparatus for extended ultraviolet femtosecond time-resolved photoemission spectroscopy,” Rev. Sci. Instrum. 72, 30–35 (2001).
[CrossRef]

Spicer, W. E.

J. N. Miller, D. T. Ling, P. M. Stefan, D. L. Weissman, M. L. Shek, I. Lindau, and W. E. Spicer, “Synchrotron radiation studies of CO and H2O adsorbed on Pt,” Phys. Rev. B 24, 1917–1926 (1981).
[CrossRef]

D. M. Collins and W. E. Spicer, “The adsorption of CO, O2 and H2 on Pt. II. Ultraviolet photoelectron spectroscopy studies,” Surf. Sci. 69, 114–132 (1977).
[CrossRef]

Spielmann, Ch.

Ch. Spielmann, N. H. Burnett, S. Sartania, R. Koppitsch, M. Schnürer, C. Kan, M. Lenzner, P. Wobrauschek, and F. Krausz, “Generation of coherent x-rays in the water window using 5-femtosecond laser pulses,” Science 278, 661–664 (1997).
[CrossRef]

Spieweck, M.

P. Siffalovic, M. Drescher, M. Spieweck, T. Wiesenthal, Y. C. Lim, R. Weidner, A. Elizarov, and U. Heinzmann, “Laser-based apparatus for extended ultraviolet femtosecond time-resolved photoemission spectroscopy,” Rev. Sci. Instrum. 72, 30–35 (2001).
[CrossRef]

Starczewski, T.

C.-G. Wahlström, J. Larsson, A. Persson, T. Starczewski, S. Svanberg, P. Salières, Ph. Balcou, and A. L’Huillier, “High-order harmonic generation in rare gases with an intense short-pulse laser,” Phys. Rev. A 48, 4709–4720 (1993).
[CrossRef] [PubMed]

Stefan, P. M.

J. N. Miller, D. T. Ling, P. M. Stefan, D. L. Weissman, M. L. Shek, I. Lindau, and W. E. Spicer, “Synchrotron radiation studies of CO and H2O adsorbed on Pt,” Phys. Rev. B 24, 1917–1926 (1981).
[CrossRef]

Steinmann, W.

D. Rieger, R. D. Schnell, and W. Steinmann, “Angular distribution patterns of photoelectrons from orbitals of CO adsorbed on Ni(100), Pt(111) and Pt(110),” Surf. Sci. 143, 157–176 (1984).
[CrossRef]

Stener, M.

M. Stener, P. Decleva, I. Cacelli, R. Moccia, and R. Montuoro, “Response function study of CO photoionization: ab initio SCF and density functional results,” Chem. Phys. 272, 15–25 (2001).
[CrossRef]

M. Stener and P. Decleva, “Time-dependent density functional calculations of molecular photoionization cross sections: N2 and PH3,” J. Chem. Phys. 112, 10871–10879 (2000).
[CrossRef]

Stöhr, J.

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

D. A. Shirley, J. Stöhr, P. S. Wehner, R. S. Williams, and G. Apai, “Photoemission from noble metals and adsorbates using synchrotron radiation,” Phys. Scr. 16, 398–413 (1977).
[CrossRef]

G. Apai, P. S. Wehner, R. S. Williams, J. Stöhr, and D. A. Shirley, “Orientation of CO on Pt(111) and Ni(111) surfaces from angle-resolved photoemission,” Phys. Rev. Lett. 37, 1497–1500 (1976).
[CrossRef]

Svanberg, S.

C.-G. Wahlström, J. Larsson, A. Persson, T. Starczewski, S. Svanberg, P. Salières, Ph. Balcou, and A. L’Huillier, “High-order harmonic generation in rare gases with an intense short-pulse laser,” Phys. Rev. A 48, 4709–4720 (1993).
[CrossRef] [PubMed]

Tempea, G.

M. Schnürer, Z. Cheng, M. Hentschel, G. Tempea, P. Kalman, Th. Brabec, and F. Krausz, “Absorption-limited generation of coherent ultrashort soft x-ray pulses,” Phys. Rev. Lett. 83, 722–725 (1999).
[CrossRef]

Tobey, R.

M. Bauer, C. Lei, K. Read, R. Tobey, J. Gland, M. M. Murnane, and H. C. Kapteyn, “Direct observation of surface chemistry using ultrafast soft-x-ray pulses,” Phys. Rev. Lett. 87, 025501 (2001).
[CrossRef]

Traum, M. M.

C. W. Seabury, T. N. Rhodin, M. M. Traum, R. Benbow, and Z. Hurych, “Angle-resolved polarization-dependent photoemission studies of carbon monoxide on iridium surfaces,” Surf. Sci. 97, 363–376 (1980).
[CrossRef]

Tsuneyuki, S.

H. Aizawa and S. Tsuneyuki, “First-principle study of CO bonding to Pt(111): validity of the Blyholder model,” Surf. Sci. 399, L364–L370 (1998).
[CrossRef]

Wahlström, C.-G.

C.-G. Wahlström, J. Larsson, A. Persson, T. Starczewski, S. Svanberg, P. Salières, Ph. Balcou, and A. L’Huillier, “High-order harmonic generation in rare gases with an intense short-pulse laser,” Phys. Rev. A 48, 4709–4720 (1993).
[CrossRef] [PubMed]

Wang, H.

Z. Chang, A. Rundquist, H. Wang, M. M. Murnane, and H. C. Kapteyn, “Generation of coherent soft x-rays at 2.7 nm using high harmonics,” Phys. Rev. Lett. 79, 2967–2970 (1997).
[CrossRef]

Wassdahl, N.

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

Wehner, P. S.

D. A. Shirley, J. Stöhr, P. S. Wehner, R. S. Williams, and G. Apai, “Photoemission from noble metals and adsorbates using synchrotron radiation,” Phys. Scr. 16, 398–413 (1977).
[CrossRef]

G. Apai, P. S. Wehner, R. S. Williams, J. Stöhr, and D. A. Shirley, “Orientation of CO on Pt(111) and Ni(111) surfaces from angle-resolved photoemission,” Phys. Rev. Lett. 37, 1497–1500 (1976).
[CrossRef]

Weidner, R.

P. Siffalovic, M. Drescher, M. Spieweck, T. Wiesenthal, Y. C. Lim, R. Weidner, A. Elizarov, and U. Heinzmann, “Laser-based apparatus for extended ultraviolet femtosecond time-resolved photoemission spectroscopy,” Rev. Sci. Instrum. 72, 30–35 (2001).
[CrossRef]

Weinelt, M.

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

Weissman, D. L.

J. N. Miller, D. T. Ling, P. M. Stefan, D. L. Weissman, M. L. Shek, I. Lindau, and W. E. Spicer, “Synchrotron radiation studies of CO and H2O adsorbed on Pt,” Phys. Rev. B 24, 1917–1926 (1981).
[CrossRef]

Wiell, T.

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

Wiesenthal, T.

P. Siffalovic, M. Drescher, M. Spieweck, T. Wiesenthal, Y. C. Lim, R. Weidner, A. Elizarov, and U. Heinzmann, “Laser-based apparatus for extended ultraviolet femtosecond time-resolved photoemission spectroscopy,” Rev. Sci. Instrum. 72, 30–35 (2001).
[CrossRef]

Williams, R. S.

D. A. Shirley, J. Stöhr, P. S. Wehner, R. S. Williams, and G. Apai, “Photoemission from noble metals and adsorbates using synchrotron radiation,” Phys. Scr. 16, 398–413 (1977).
[CrossRef]

G. Apai, P. S. Wehner, R. S. Williams, J. Stöhr, and D. A. Shirley, “Orientation of CO on Pt(111) and Ni(111) surfaces from angle-resolved photoemission,” Phys. Rev. Lett. 37, 1497–1500 (1976).
[CrossRef]

Winstedad, C. L.

T. J. Gil, C. L. Winstedad, J. A. Sheehy, R. E. Farren, and P. W. Lanhoff, “New theoretical perspectives on molecular shape resonances: Feshbach–Fano methods for Mulliken orbital analysis of photoionization continua,” Phys. Scr. T31, 179–188 (1990).
[CrossRef]

Wobrauschek, P.

Ch. Spielmann, N. H. Burnett, S. Sartania, R. Koppitsch, M. Schnürer, C. Kan, M. Lenzner, P. Wobrauschek, and F. Krausz, “Generation of coherent x-rays in the water window using 5-femtosecond laser pulses,” Science 278, 661–664 (1997).
[CrossRef]

Appl. Phys. A (1)

A. Nilsson, N. Wassdahl, M. Weinelt, O. Karis, T. Wiell, P. Bennich, J. Hasselström, A. Föhlisch, J. Stöhr, and M. Samant, “Local probing of the surface chemical bond using x-ray emission spectroscopy,” Appl. Phys. A 65, 147–154 (1997).
[CrossRef]

Chem. Phys. (1)

M. Stener, P. Decleva, I. Cacelli, R. Moccia, and R. Montuoro, “Response function study of CO photoionization: ab initio SCF and density functional results,” Chem. Phys. 272, 15–25 (2001).
[CrossRef]

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[CrossRef]

M. Stener and P. Decleva, “Time-dependent density functional calculations of molecular photoionization cross sections: N2 and PH3,” J. Chem. Phys. 112, 10871–10879 (2000).
[CrossRef]

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[CrossRef]

Phys. Rev. A (3)

C.-G. Wahlström, J. Larsson, A. Persson, T. Starczewski, S. Svanberg, P. Salières, Ph. Balcou, and A. L’Huillier, “High-order harmonic generation in rare gases with an intense short-pulse laser,” Phys. Rev. A 48, 4709–4720 (1993).
[CrossRef] [PubMed]

L. Nugent-Glandorf, M. Scheer, M. Krishnamurthy, J. W. Odom, and S. R. Leone, “Photoelectron spectroscopic determination of the energy bandwidths of high-order harmonics (7th-55th) produced by an ultrafast laser in neon,” Phys. Rev. A 62, 023812 (2000).
[CrossRef]

S. K. Semenov, N. A. Cherepkov, G. H. Fecher and G. Schönhense, “Generalization of the atomic random-phase-approximation method for diatomic molecules: N2 photoionization cross-section calculations,” Phys. Rev. A 61, 032704 (2000).
[CrossRef]

Phys. Rev. B (3)

P. Budau and G. Raseev, “Shape resonances in photoemission for CO molecules adsorbed on metallic surfaces: a model including backscattering,” Phys. Rev. B 51, 16993–17006 (1995).
[CrossRef]

J. N. Miller, D. T. Ling, P. M. Stefan, D. L. Weissman, M. L. Shek, I. Lindau, and W. E. Spicer, “Synchrotron radiation studies of CO and H2O adsorbed on Pt,” Phys. Rev. B 24, 1917–1926 (1981).
[CrossRef]

F. Greuter, D. Heskett, E. W. Plummer, and H.-J. Freund, “Chemisorption of CO on Co(0001). Structure and electronic properties,” Phys. Rev. B 27, 7117–7135 (1983).
[CrossRef]

Phys. Rev. Lett. (9)

D. E. Eastman and J. K. Cashion, “Photoemission energy-level measurements of chemisorbed CO and O on Ni,” Phys. Rev. Lett. 27, 1520–1523 (1971).
[CrossRef]

J. W. Davenport, “Ultraviolet photoionization cross sections for N2 and CO,” Phys. Rev. Lett. 36, 945–949 (1976).
[CrossRef]

G. Apai, P. S. Wehner, R. S. Williams, J. Stöhr, and D. A. Shirley, “Orientation of CO on Pt(111) and Ni(111) surfaces from angle-resolved photoemission,” Phys. Rev. Lett. 37, 1497–1500 (1976).
[CrossRef]

M. Schnürer, Z. Cheng, M. Hentschel, G. Tempea, P. Kalman, Th. Brabec, and F. Krausz, “Absorption-limited generation of coherent ultrashort soft x-ray pulses,” Phys. Rev. Lett. 83, 722–725 (1999).
[CrossRef]

A. L’Huillier and Ph. Balcou, “High-order harmonic generation in rare gases with a 1-ps 1053-nm laser,” Phys. Rev. Lett. 70, 774–777 (1993).
[CrossRef] [PubMed]

P. B. Corkum, “Plasma perspective on strong-field multiphoton ionization,” Phys. Rev. Lett. 71, 1994–1997 (1993).
[CrossRef] [PubMed]

J. L. Krause, K. J. Schafer, and K. C. Kulander, “High-order harmonic generation from atoms and ions in the high intensity regime,” Phys. Rev. Lett. 68, 3535–3538 (1992).
[CrossRef] [PubMed]

M. Bauer, C. Lei, K. Read, R. Tobey, J. Gland, M. M. Murnane, and H. C. Kapteyn, “Direct observation of surface chemistry using ultrafast soft-x-ray pulses,” Phys. Rev. Lett. 87, 025501 (2001).
[CrossRef]

Z. Chang, A. Rundquist, H. Wang, M. M. Murnane, and H. C. Kapteyn, “Generation of coherent soft x-rays at 2.7 nm using high harmonics,” Phys. Rev. Lett. 79, 2967–2970 (1997).
[CrossRef]

Phys. Scr. (2)

T. J. Gil, C. L. Winstedad, J. A. Sheehy, R. E. Farren, and P. W. Lanhoff, “New theoretical perspectives on molecular shape resonances: Feshbach–Fano methods for Mulliken orbital analysis of photoionization continua,” Phys. Scr. T31, 179–188 (1990).
[CrossRef]

D. A. Shirley, J. Stöhr, P. S. Wehner, R. S. Williams, and G. Apai, “Photoemission from noble metals and adsorbates using synchrotron radiation,” Phys. Scr. 16, 398–413 (1977).
[CrossRef]

Rev. Sci. Instrum. (2)

P. Siffalovic, M. Drescher, M. Spieweck, T. Wiesenthal, Y. C. Lim, R. Weidner, A. Elizarov, and U. Heinzmann, “Laser-based apparatus for extended ultraviolet femtosecond time-resolved photoemission spectroscopy,” Rev. Sci. Instrum. 72, 30–35 (2001).
[CrossRef]

D. Riedel, J. L. Hernandez-Pozos, R. E. Palmer, S. Baggott, K. W. Kolasinski, and J. S. Foord, “Tunable pulsed vacuum ultraviolet light source for surface science and materials spectroscopy based on high order harmonic generation,” Rev. Sci. Instrum. 72, 1977–1983 (2001).
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Science (1)

Ch. Spielmann, N. H. Burnett, S. Sartania, R. Koppitsch, M. Schnürer, C. Kan, M. Lenzner, P. Wobrauschek, and F. Krausz, “Generation of coherent x-rays in the water window using 5-femtosecond laser pulses,” Science 278, 661–664 (1997).
[CrossRef]

Solid State Commun. (1)

P. Hofmann, S. R. Bare, N. V. Richardson, and D. A. King, “Orientation of chemisorped species from orthogonal-plane ARUPS: tilted CO on Pt{110} and upright CO on Pt{111},” Solid State Commun. 42, 645–651 (1982).
[CrossRef]

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[CrossRef]

H. Aizawa and S. Tsuneyuki, “First-principle study of CO bonding to Pt(111): validity of the Blyholder model,” Surf. Sci. 399, L364–L370 (1998).
[CrossRef]

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[CrossRef]

S. R. Bare, K. Griffiths, P. Hoffmann, D. A. King, G. L. Nyberg, N. V. Richardson, “A synchrotron radiation study of the electronic and geometric structure of CO on Pt{110},” Surf. Sci. 120, 367–375 (1982).
[CrossRef]

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[CrossRef]

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[CrossRef]

D. Rieger, R. D. Schnell, and W. Steinmann, “Angular distribution patterns of photoelectrons from orbitals of CO adsorbed on Ni(100), Pt(111) and Pt(110),” Surf. Sci. 143, 157–176 (1984).
[CrossRef]

C. W. Seabury, T. N. Rhodin, M. M. Traum, R. Benbow, and Z. Hurych, “Angle-resolved polarization-dependent photoemission studies of carbon monoxide on iridium surfaces,” Surf. Sci. 97, 363–376 (1980).
[CrossRef]

Other (4)

Data sheet provided for the toroid grating type, 540 00 210 (ISA Instruments S.A., Inc., Grasbrunn, Germany).

H. Ibach and H. Lüth, Festkörperphysik (Springer-Verlag, Berlin, 1995).

G. Tsilimis, G. Fecher, J. Braun, J. Kutzner, and H. Zacharias, “Direct observation of final states in photoemission from Pt(111) excited by laser generated XUV radiation,” submitted to Europhys. Lett.

S. Hüfner, Photoelectron Spectroscopy (Springer-Verlag, Heidelberg, 1996).

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Figures (8)

Fig. 1
Fig. 1

High-harmonic spectra generated in argon, neon, and helium; 30-fs laser pulses of 0.65-mJ pulse energy were used. The backing pressures for the EUV source were 120 mbar for argon, 200 mbar for neon, and 320 mbar for helium. The generated EUV radiation was detected with a MCP detector.

Fig. 2
Fig. 2

Harmonic conversion efficiencies for argon (filled squares) and neon (open circles).

Fig. 3
Fig. 3

Energy widths of high harmonics from the 17th to the 51st order obtained in argon (filled squares) and neon (open circles). The dashed curve is intended to guide the eye. The calculated energy resolution of the monochromator with a 1-mm slit width (solid curve) agrees well with the experimentally determined energy resolution from photoemission data (stars).

Fig. 4
Fig. 4

Tunability of the high-harmonic photon source. The hatched areas represent energy regions in which radiation can be generated on the basis of odd harmonics and the width results of Fig. 3. Electron kinetic energy measurements of the photoemission from Pt(111) were used to verify the tuning. The position of the Fermi edge has been analyzed for different monochromator settings. The filled circles give the experimental results. The dashed line is a theoretically predicted curve when a broadband light source is used. The fine-tuning range is ∼1 eV or more and is larger than given by the harmonic widths of the above figure.

Fig. 5
Fig. 5

Photoemission results for a Ni(111) surface. Top, clean Ni(111) spectrum obtained with a He i discharge lamp (hν=21.2 eV) and recorded with an energy-dispersive analyzer. Middle, spectrum recorded by use of the 25th harmonic at hν=38.8 eV. Bottom, oxygen-covered Ni(111) spectrum taken under the same conditions as the middle spectrum.

Fig. 6
Fig. 6

Photoelectron spectra of (top) clean and (middle) c(4×2)-2CO covered Pt(111) measured with high-harmonic radiation hν of 26.4 and 26.6 eV, respectively (19th harmonic). A resonance originating from the secondary electron emission on the clean surface (EB=-10.5 eV) interferes with the CO-induced signals on the CO-covered surface at this photon energy. The bottom spectrum is recorded at a photon energy of 30.0 eV. The secondary electron resonance is now shifted out of the region of the CO-induced signal structure. The dotted lines in the spectra give the signal contributions of the CO 4σ, 5σ, and 1π valence resonances. The contribution of the secondary electron resonance is given by the dashed curve. The thick solid curve represents the overall fit to the measured signal curve. Additionally, the bottom spectrum, shows how the relative photoemission cross section I has been determined. It is defined as the quotient of the peak area A and the background area U: I=A/U.

Fig. 7
Fig. 7

Photoemission cross section of the CO-induced 4σ, 5σ, and 1π states for c(4×2)-2CO Pt(111) using p-polarized high-harmonic radiation. Data points with (filled circles, solid curve) and without (open circles, dashed curve) taking the final-state resonance into account are presented. This resonance causes additional structure in the cross section.

Fig. 8
Fig. 8

Level scheme for the 3σ2π* enhanced ionization of the 1π state in CO/Pt(111).

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