Electron energy-loss spectra of coupled electronic states: Effects of Rydberg-valence interactions in O2

Physical Review A - Atomic, Molecular, and Optical Physics

Volumn 63, Issue 2, 2001, Pages 022707-022701

  Lewis, B R ^a   England, J P ^a   Gibson, S T ^a   Brunger, M J ^b   Allan, M ^c  

^a AUSTRALIAN NATIONAL UNIVERSITY   (Australia)

^b FLINDERS UNIVERSITY   (Australia)

^c UNIVERSITY OF FRIBOURG   (Switzerland)

Author keywords

[No Author keywords available]

Indexed keywords

ELECTRON ENERGY LOSSES; MOLECULAR EXCITATION ENERGIES; QUANTUM NUMBERS; RYDBERG-VALENCE INTERACTIONS; TRANSITION MOMENTS;

APPROXIMATION THEORY; ELECTRON ENERGY LOSS SPECTROSCOPY; ELECTRON RESONANCE; ELECTRON SCATTERING; ELECTRON TRANSITIONS; KINEMATICS; MOLECULAR VIBRATIONS; PHOTODISSOCIATION; POTENTIAL ENERGY; QUANTUM THEORY; WAVE EQUATIONS;

ELECTRON ENERGY LEVELS;

EID: 0035251345     PISSN: 10502947     EISSN: None     Source Type: Journal    
DOI: 10.1103/PhysRevA.63.022707     Document Type: Article

References (102)

1. D. C. Cartwright, W. J. Hunt, W. Williams, S. Trajmar, and W. A. Goddard III, Phys. Rev. A 8, 2436 (1973).
2. T. A. York and J. Comer, J. Phys. B 16, 3627 (1983).
3. J. C. Nickel, P. W. Zetner, G. Shen, and S. Trajmar, J. Phys. E 22, 730 (1989), and references therein.
4. M. Allan, J. Phys. B 28, 4329 (1995).
5. M. J. Brunger and P. J. O. Teubner, Phys. Rev. A 41, 1413 (1990), and references therein.
6. A. G. Middleton, M. J. Brunger, P. J. O. Teubner, M. W. B. Anderson, C. J. Noble, G. Woeste, K. Blum, and C. Fullerton, J. Phys. B 27, 4057 (1994).
7. M. A. Dillon, in Creation and Detection of the Excited State, edited by A. A. Lamola (Marcel Dekker, New York, 1971), pp. 375-428.
8. A. Skerbele and E. N. Lassettre, J. Chem. Phys. 44, 4066 (1966).
9. J. P. Doering, J. Chem. Phys. 71, 20 (1979).
10. E. N. Lassettre, A. Skerbele, M. A. Dillon, and K. J. Ross, J. Chem. Phys. 48, 5066 (1968).
11. W. Harshbarger, W. R. Skerbele, and E. N. Lassettre, J. Chem. Phys. 54, 3784 (1971).
12. E. N. Lassettre, Can. J. Chem. 47, 1733 (1969), and references therein.
13. E. N. Lassettre and A. Skerbele, J. Chem. Phys. 54, 1597 (1971).
14. K. L. Klump and E. N. Lassettre, J. Chem. Phys. 60, 4830 (1974).
15. 2 is labeled as the B′ state by some authors. We prefer the nomenclature suggested by K. P. Huber and G. Herzberg, Molecular Spectra and Molecular Structure, IV Constants of Diatomic Molecules (Van Nostrand Reinhold, New York, 1979), p. 494.
16. J. Geiger and B. Schröder, J. Chem. Phys. 49, 740 (1968).
17. M. Dillon, M. Kimura, R. J. Buenker, G. Hirsch, Y. Li, and L. Chantranupong, J. Chem. Phys. 102, 1561 (1995).
18. R. J. Buenker and S. D. Peyerimhoff, Chem. Phys. Lett. 34, 225 (1975).
19. R. J. Buenker and S. D. Peyerimhoff, Chem. Phys. 8, 324 (1975).
20. R. J. Buenker and S. D. Peyerimhoff, Chem. Phys. Lett. 36, 415 (1975).
21. R. J. Buenker, S. D. Peyerimhoff, and M. Peric, Chem. Phys. Lett. 42, 383 (1976).
22. Y. Tanaka, J. Chem. Phys. 20, 1728 (1952).
23. R. D. Hudson, Rev. Geophys. Space Phys. 9, 305 (1972).
24. W. F. Chan, G. Cooper, and C. E. Brion, Chem. Phys. 170, 99 (1993).
25. B. R. Lewis, S. T. Gibson, M. Emami, and J. H. Carver, J. Quant. Spectrosc. Radiat. Transfer 40, 1 (1988).
26. M. Yoshimine, J. Chem. Phys. 64, 2254 (1976).
27. D. H. Katayama, S. Ogawa, M. Ogawa, and Y. Tanaka, J. Chem. Phys. 67, 2132 (1977).
28. P. S. Julienne, D. Neumann, and M. Krauss, J. Chem. Phys. 64, 2990 (1976).
29. L. C. Lee, T. G. Slanger, G. Black, and R. L. Sharpless, J. Chem. Phys. 67, 5602 (1977).
30. S. T. Gibson and B. R. Lewis, J. Electron Spectrosc. Relat. Phenom. 80, 9 (1996).
31. J. B. Nee and P. C. Lee, J. Phys. Chem. A 101, 6653 (1997).
32. P. C. Lee and J. B. Nee, J. Chem. Phys. 112, 1763 (2000).
33. S. L. Guberman and A. Dalgarno, J. Geophys. Res. 84, 4437 (1979).
34. A. C. Allison, S. L. Guberman, and A. Dalgarno, J. Geophys. Res. 87, 923 (1982).
35. J. P. England, B. R. Lewis, S. T. Gibson, and M. L. Ginter, J. Chem. Phys. 104, 2765 (1996).
36. u symmetry is introduced in Sec. IV B.
37. E. F. van Dishoeck, M. C. van Hemert, A. C. Allison, and A. Dalgarno, J. Chem. Phys. 81, 5709 (1984).
38. F. H. Mies, Mol. Phys. 41, 953 (1980).
39. F. H. Mies, Mol. Phys. 41, 973 (1980).
40. L. Torop, D. G. McCoy, A. J. Blake, J. Wang, and T. Scholz, J. Quant. Spectrosc. Radiat. Transfer 38, 9 (1987).
41. J. Wang, D. G. McCoy, A. J. Blake, and L. Torop, J. Quant. Spectrosc. Radiat. Transfer 38, 19 (1987).
42. J. Wang, A. J. Blake, D. G. McCoy, and L. Torop, J. Quant. Spectrosc. Radiat. Transfer 40, 501 (1988).
43. E. N. Lassettre, S. M. Silverman, and M. E. Krasnow, J. Chem. Phys. 40, 1261 (1964).
44. S. M. Silverman and E. N. Lassettre, J. Chem. Phys. 40, 2922 (1964).
45. R. H. Huebner, R. J. Celotta, S. R. Mielczarek, and C. E. Kuyatt, J. Chem. Phys. 63, 241 (1975).
46. C. E. Brion, K. H. Tan, M. J. van der Wiel, and Ph. E. van der Leeuw, J. Electron Spectrosc. Relat. Phenom. 17, 101 (1979).
47. S. Trajmar, W. Williams, and A. Kuppermann, J. Chem. Phys. 56, 3759 (1972).
48. S. Trajmar, D. C. Cartwright, and R. I. Hall, J. Chem. Phys. 65, 5275 (1976).
49. S. Trajmar, D. C. Cartwright, and W. Williams, Phys. Rev. A 4, 1482 (1971).
50. S. Trajmar, D. F. Register, and A. Chutjian, Phys. Rep. 97, 219 (1983).
51. S. Trajmar and D. C. Cartwright, in Electron Molecule Interactions and Their Applications, edited by L. G. Christophorou (Academic, New York, 1984), Vol. 1, pp. 154-250.
52. Y. Itikawa, A. Ichimura, K. Onda, K. Sakimoto, K. Takayanagi, Y. Hatano, M. Hayashi, H. Nishimura, and S. Tsurubuchi, J. Phys. Chem. Ref. Data 18, 23 (1989).
53. T. W. Shyn, C. J. Sweeney, A. Grafe, and W. E. Sharp, Phys. Rev. A 50, 4794 (1994).
54. T. W. Shyn, C. J. Sweeney, and A. Grafe, Phys. Rev. A 49, 3680 (1994).
55. K. Wakiya, J. Phys. B 11, 3913 (1978).
56. H. A. Bethe, Ann. Phys. (Leipzig) 5, 325 (1930).
57. E. N. Lassettre, A. Skerbele, and M. A. Dillon, J. Chem. Phys. 50, 1829 (1969).
58. M. Shugard and A. U. Hazi, Phys. Rev. A 12, 1895 (1975).
59. D. C. Cartwright, N. A. Fiamengo, W. Williams, and S. Trajmar, J. Phys. B 9, L419 (1976).
60. M. Allan, J. Phys. B 25, 1559 (1992).
61. M. Allan, Chem. Phys. Lett. 225, 156 (1994).
62. However, traditional units of eV and A are used for energy and internuclear distance, respectively, in the presentation of parameters and results.
63. N. F. Lane, Rev. Mod. Phys. 52, 29 (1980).
64. In fact, according to B. I. Schneider, Phys. Rev. A 14, 1923 (1976), the Born-Oppenheimer approximation may also be applicable in cases of resonant scattering where the adiabatic-nuclei approximation fails.
65. E. S. Chang and U. Fano, Phys. Rev. A 6, 173 (1972).
66. M. A. Morrison, Aust. J. Phys. 36, 239 (1983).
67. Consistent with the assumption of a short collision time, the incident electron spends little time near the nuclei and does not contribute to the electronic potential-energy curves governing the nuclear motion.
68. This suggestion follows from consideration of a fixed-nuclei scattering amplitude with slow explicit dependences on R and υ′, within the framework of the R-centroid approximation [R. W. Nicholls, J. Quant. Spectrosc. Radiat. Transfer 2, 433 (1962)].
69. C. E. Brion and A. Hamnett. Adv. Chem. Phys. 45, 1 (1981).
70. H. Lefebvre-Brion and R. W. Field, Perturbations in the Spectra of Diatomic Molecules (Academic, Orlando, 1986), pp. 29-40, 209-212, 344-349.
71. A. C. Allison, A. Dalgarno, and N. W. Pasachoff, Planet. Space Sci. 19, 1463 (1971).
72. B. R. Lewis, L. Berzins, and J. H. Carver, J. Quant. Spectrosc. Radiat. Transf. 36, 209 (1986).
73. B. R. Lewis, S. S. Banerjee, and S. T. Gibson, J. Chem. Phys. 102, 6631 (1995).
74. Throughout this work, we use the hat to distinguish the pure diabatic electronic state (e.g., B́) from the corresponding adiabatic electronic state (e.g., B), with the convention that the diabatic and adiabatic states become indistinguishable at large R values where the coupling is taken to approach zero.
75. B. R. Lewis, S. T. Gibson, M. Emami, and J. H. Carver, J. Quant. Spectrosc. Radiat. Transfer 40, 469 (1988).
76. B. R. Lewis and J. P. England (unpublished).
77. J. P. England, B. R. Lewis, and M. L. Ginter, J. Chem. Phys. 105, 1754 (1996).
78. Y. Li, M. Honigmann, K. Bhanuprakash, G. Hirsch, R. J. Buenker, M. A. Dillon, and M. Kimura, J. Chem. Phys. 96, 8314 (1992).
79. B. R. Johnson, J. Chem. Phys. 69, 4678 (1978).
80. P. C. Cosby (private communication).
81. u Rydberg states, should be adequate to describe the E′(0) level.
82. K. Dressler, Ann. Isr. Phys. Soc. 6, 141 (1983).
83. E is the separation of the first vibrational levels of the upper adiabatic state formed by the avoided crossing. This parameter provides a measure of the applicability of the adiabatic or diabatic pictures to the mixed states. Near adiabatic behavior occurs for ζ ≫ 1, near-diabatic behavior for ζ ≪ 1, while for ζ ≈ 1, the amount of basis-state mixing in either representation is large.
84. The energy scale for the CC calculations is expected to be reliable since the calculations were based on very-high-resolution optical spectra of known accuracy.
85. The uncertainty in the CC oscillator strengths is expected to be ∼5%, comprising contributions from uncertainties in the very-high-resolution optical oscillator strengths on which the CC model is based, together with uncertainties in the fitting procedure. Furthermore, an extrapolation uncertainty can be expected in the Bethe-Born factor used by Chan et al. [24] to normalize their experimental oscillator strengths, which was based on a calibration point at 26-eV energy loss.
86. Except for the broader features, the intensities are height-width products determined by fitting Fano profiles to the computed rotationless resonances. Intensities of the broader features (B ←X, J←X) are effective height-width products determined as 0.637X the directly integrated rotationless cross sections. As a result, the optical-limit intensity ratios plotted in Fig. 4 differ, in general, from the corresponding ratios of the integrated intensities, but the r dependence of the ratios is insensitive to the definition of the intensities.
87. H. Park, P. J. Miller, W. A. Chupka, and S. D. Colson, J. Chem. Phys. 89, 6676 (1988).
88. r-2 eV, θ=90° spectrum militates against any significant contribution from this source.
89. r=2 eV, θ=90° spectrum, corresponding to the highest momentum-transfer values plotted in Fig. 6, the scaling factors employed were determined by matching the relative intensities of the peaks for only this spectrum, after the application of small computed corrections for the effects of the optically allowed transitions.
90. Initial experimental intensity ratios were determined using the width-height products of peaks in the EEL spectra. These were converted into ratios suitable for comparison with the computed values of Fig. 4 using correction factors determined by the analysis of instrumentally-degraded theoretical spectra.
91. B. R. Lewis (unpublished).
92. 2 because of rapid fall off in the relative F←X intensities.
93. Since the J←X feature at 9.15 eV exists only as an inflection in the experimental cross section, the width of this feature was assumed to be independent of the scattering conditions, and equal to the theoretical value, in estimating the integrated intensities.
94. - systems in the EEL spectra without reference to experiment. Therefore, the calculated F←X(0,0) to E←X(0,0) intensity ratios in Fig. 8 were obtained from the computed constituent spectra of Fig. 5(a), each of which has been optimized by comparison with the experimental spectra of Fig. 5(b).
95. - states. Energies for these states that have been predicted recently [B. R. Lewis, S. T. Gibson, S. S. Banerjee, and H. Lefebvre-Brion, J. Chem. Phys. 113, 2214 (2000)] are well separated from the F(0) energy.
96. P. C. Hill, Ph.D. thesis, The Australian National University, 1991.
97. R. J. Buenker and Y. Li (private communication).
98. The ab initio values [97] plotted in Fig. 9 apply at an internuclear distance r = 2.3 a.u.
99. r = 2 eV, i.e., about an order of magnitude greater than the vibrational spacing. We assume that the AN approximation remains valid under this condition.
100. r=2 eV. θ=90° spectrum in Fig. 5(b), presumably due to the effects of negative-ion resonances.
101. M. Ogawa, K. R. Yamawaki, A. Hashizume, and Y. Tanaka, J. Mol. Spectrosc. 55, 425 (1975).
102. - GETM to vary from the optical value.