Two-photon dissociation of vibrationally excited HD/sup +/: The inhomogeneous differential equation approach

Journal Article · Fri Aug 01 04:00:00 EDT 1986 · J. Chem. Phys.; (United States)

OSTI ID:5522184

Laughlin, C; Datta, K K; Chu, S

We extend the inhomogenous-differential-equation (IDE) approach of Dalgarno and Lewis for a detailed study of two-photon dissociation (TPD) of HD/sup +/ from high vibrational levels of the 1s-italicsigma/sub g-italic/ electronic state. Contrary to the H/sup +//sub 2/ case, where the TPD cross sections sigma/sup (2)//sub L-italic/ are largest near TPD thresholds and decrease monotonically with increasing photon energy, the HD/sup +/ cross sections are characterized by rich resonant and interference structures. We present sigma/sup (2)//sub L-italic/ results for TPD from the initial v-italic/sub i-italic/ = 6, 8, 10, 12, 14, 16, and j-italic/sub i-italic/ = 0 levels as well as from v-italic/sub i-italic/ = 14, j-italic/sub i-italic/ = 0, 2, 4 levels for a wide range of wavelengths of linearly polarized radiation accessible by CO/sub 2/ and CO lasers. It is found that while there are four TPD pathways, the channel 1s-italicsigma/sub g-italic/(v-italic/sub i-italic/ j-italic/sub i-italic/)..--> omega.. 1s-italicsigma/sub g-italic/(v-italic, j-italic = j-italic/sub i-italic/ +- 1) ..--> omega..2p-italicsigma/sub u-italic/(k-italic, j-italic/sub //sub f-italic/ = j-italic +- 1) dominates the two-photon process in most of the cases we have studied. Further, the results show that sigma/sup (2)//sub L-italic/ increases rather rapidly as the initial vibrational quantum number v-italic/sub i-italic/ increases, indicating that the hereronuclear diatomic molecules in high vibrational levels can be efficiently two-photon dissociated by IR lasers. Consequently molecular structures near the dissociation limit may be conveniently probed by two-photon spectroscopy: as has indeed been demonstrated recently by experiments.

• Research Organization: Department of Chemistry, University of Kansas, Lawrence, Kansas 66045
• OSTI ID: 5522184
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 85:3; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
CATIONS
CHARGED PARTICLES
DEUTERIDES
DEUTERIUM COMPOUNDS
DISSOCIATION
ENERGY LEVELS
EXCITED STATES
HYDROGEN COMPOUNDS
HYDROGEN DEUTERIDE
IONS
MULTI-PHOTON PROCESSES
VIBRATIONAL STATES