Vibrationally resolved cross sections for single-photon ionization of LiH

Citation
Mfv. Lundsgaard et H. Rudolph, Vibrationally resolved cross sections for single-photon ionization of LiH, J CHEM PHYS, 111(15), 1999, pp. 6724-6734
Citations number
44
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
JOURNAL OF CHEMICAL PHYSICS
ISSN journal
0021-9606 → ACNP
Volume
111
Issue
15
Year of publication
1999
Pages
6724 - 6734
Database
ISI
SICI code
0021-9606(19991015)111:15<6724:VRCSFS>2.0.ZU;2-Z
Abstract
Ab initio studies of the single-photon ionization of LiH(X (1)Sigma(+)) lea ding to LiH+(X (2)Sigma(+)) are reported. The process is studied as functio n of the internuclear distance (2 a.u.-6 a.u.) and the kinetic energy of th e electron (0.05 eV-10 eV). The calculations are based on the so-called ite rative Schwinger approach which is implemented within the frozen-core singl e center approximation. By comparing vibrationally resolved cross sections calculated beyond and within the Franck-Condon principle we find, that the Franck-Condon principle applies relatively well to the present photoionizat ion process. The vibrational wave functions needed for these calculations a re obtained from very accurate CI-potentials, also reported in this paper. For LiH the first 10 vibrational spacings are found to agree with the exper imental data within 0.2%. Photoelectron spectra (PES) calculated under simu lated experimental conditions suggest that photoionization experiments on L iH may yield information on the vibrational structure of LiH+. The calculat ed permanent dipole moment of the LiH ground state shows strong influence o f the ion-pair channel (Li+H-). (C) 1999 American Institute of Physics. [S0 021-9606(99)30139-2].