Home

About

Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network
FAQHELPSITE MAPCONTACT US


  Advanced Search  

 
Condensed phase spectroscopy from mixed-order semiclassical molecular dynamics: Absorption, emission, and resonant Raman spectra of I2
 

Summary: Condensed phase spectroscopy from mixed-order semiclassical molecular
dynamics: Absorption, emission, and resonant Raman spectra of I2
isolated in solid Kr
M. Ovchinnikov and V. A. Apkarian
Department of Chemistry, University of California, Irvine, California 92697-2025
Received 5 August 1996; accepted 10 September 1996
A method for spectral simulations in systems of very large dimensionality via semiclassical
molecular dynamics is introduced and applied to the spectroscopy of iodine isolated in solid Kr, as
a prototype of spectroscopy in condensed media in general. The method relies on constructing
quantum correlation functions, C(t), using initial value propagators which correspond to the zeroth-
and second-order approximations in stationary phase of the exact quantum propagator. The first is
used for treating modes with high thermal occupation numbers, the lattice modes, while the second
is used for treating the guest mode. The limits of validity of the bare propagators are tested vs exact
treatments of gas phase I2, and shown to be quite broad. The mixed order simulations are then used
to reproduce the structured AX emission, the structureless BX absorption, and the intensities
in resonant Raman RR progressions of matrix isolated I2, connecting spectroscopic observables to
molecular motions. Decompositions of the supersystem correlations into system and bath are used
to provide perspectives about condensed phase spectroscopy. The system correlation can be
regarded as the sampling function for the decaying bath correlation, which in turn is a summary of
the many-body dynamics. The BX absorption spectrum is determined by the coherent ballistic

  

Source: Apkarian, V. Ara - Department of Chemistry, University of California, Irvine

 

Collections: Chemistry