Av. Shabatina et Ay. Ermilov, Modeling of the influence of solvation on the vibrational spectra of high-symmetry molecular ions, RUSS J PH C, 74(1), 2000, pp. 127-132
An ab initio quantum-chemical method was used ro study the vibrational spec
tra of Na3SbS4 in aqueous solutions. The Raman spectra of the corresponding
anion were calculated based on a tetrahedral model. First, solvent effects
were described with the use of the self-consistent reaction field model. A
t the second stage, a method for explicitly taking into account the average
electrostatic field of the ionic environment was introduced. The geometric
configuration and the frequencies of vibrations not involving dipole momen
t changes were insensitive to the parameters of the reaction field model. T
he frequencies of Fz-type vibrations (d mu/dQ not equal 0) shifted to the r
ed by values that correlated with the calculated IR band intensities. The i
onic environment model allows a neutral system to be considered. Taking int
o account the average field of counterions led to a decrease in internuclea
r distances in the complex and increased all vibrational frequencies, which
improved agreement with experiment.