In:
The Journal of Chemical Physics, AIP Publishing, Vol. 120, No. 20 ( 2004-05-22), p. 9487-9498
Abstract:
We present results of a combined theoretical and experimental study on the vibrational predissociation of the HCl dimer. On the theoretical side, photodissociation linewidths and product-state distributions for monomer stretch excited states with total angular momentum J=0 were computed, using the Fermi golden rule approximation. The resonances investigated include excitation of the hydrogen bond donor and acceptor stretches, as well as combinations of one of these modes with the intermolecular stretch and geared bend modes, for both even and odd permutation symmetry. Line strengths for the transitions from the J=1, K=0 ground state to excited states with J=0 were computed using quasibound states. On the experimental side, the photofragment angular distribution method was employed to obtain complete final-state distributions for the monomer stretch excited states. Three different transitions were probed, all starting from the lower tunneling component of the ground state: the Q0R(1) transition for excitation of the acceptor stretch and the R0Q(0) transition and unresolved Q0R branch for the donor stretch excitation. We find that, in contrast to the HF dimer, the excited-state alignment of the HCl dimer, resulting from excitation using a polarized laser beam, is completely lost on the time scale of the dissociation. The agreement between theory and experiment for the product-state distributions and line strengths is reasonable. The computed lifetimes are 1–2 orders of magnitude too small, which is attributed to a deficiency in the potential energy surface.
Type of Medium:
Online Resource
ISSN:
0021-9606
,
1089-7690
Language:
English
Publisher:
AIP Publishing
Publication Date:
2004
detail.hit.zdb_id:
3113-6
detail.hit.zdb_id:
1473050-9
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