ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
A theoretical study is reported for the dependence of the E, F 1Σ+g–X 1Σ+g (vE=0, vX) Q-branch two-photon transitions on the initial vibrational and rotational quantum numbers vX and J for H2, HD, and D2. The magnitude of the two-photon transition moment ||Mfo|| increases with vX between 0 and 2, then decreases rapidly at higher vX. This behavior is ascribed to (constructive and destructive) interference effects in the two-photon transition, which vary with the nodal behavior of the initial-state vibrational wave function. The J dependence of ||Mfo|| is most strongly affected by the changes in vibrational wave functions caused by centrifugal distortion of the vibrational potentials. At low to intermediate J, the Franck–Condon overlap improves, resulting in a slow, monotonic increase of ||Mfo|| with J. At higher J, resonant tunneling between the inner and outer wells of the E, F state introduces sharp variations in the ||Mfo|| structure. Near the top of the barrier, nonresonant tunneling in the E-state vibrational wave function causes a general decrease in ||Mfo|| with J.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.461477
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