OVERTONE SPECTRA AND INTENSITIES OF TETRAHEDRAL MOLECULES IN BOSON-REALIZATION MODELS

The stretching and bending vibrational spectrum and the intensities of infrared transitions in a tetrahedral molecule are studied in two bos on-realization models, where the interactions between stretching and b ending vibrations are described by a quadratic cross term and by Fermi resonance terms, called harmonically coupled and Fermi resonance boso n-realization model, respectively. The later is a development of our r ecent model. As an example, the two models are applied to the overtone spectrum and the intensities of silicon tetrafluorde. Those models pr ovide fits to the published experimental vibrational eigenvalues with standard deviations 1.956 cm(-1) and 0.908 cm(-1), respectively. The i ntensities of infrared transitions of its complete vibrations are calc ulated in the two models, and results show a good agreement with the o bserved data. (C) 1998 Academic Press.