CHARACTERIZATION OF TRAPPING SITES IN RELAXED RARE GAS MATRICES USING MONTE-CARLO SIMULATIONS OF INFRARED MATRIX SHIFTS
Loading...
Date
1991
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
When a chromophore is trapped inside a rare gas matrix, its characteristic vibrational frequencies are displaced from those of the free molecule. The resulting shifted infrared spectrum depends on the temperature and the nature of the vacancy site occupied by the chromophore. Application of Monte-Carlo averaging techniques to a realistic model for the chromophore-matrix interaction and a means of estimating the frequency shifts, allows us to examine the effect of the size and shape of the trapping site on the predicted spectrum. In previous work, we examined the effect on the spectrum of placing the chormophore in vacancies of different sizes in a rigid lattice. The present study also allows layers of lattice atoms surrounding the chromophore to thermally relax. In general, the shape and nature of the spectrum is dependent on the size and shape of the vacancy, and on the degree of relaxation of the surrounding lattice atoms. This paper will describes our application of this approach to the case of $SF_{6}$ molecules in Ar matrices.
Description
Author Institution: Guelph-Waterloo Centre for Graduate Work in Chemistry, University of Waterloo