A nonlinear model for highly excited vibrational energy levels of silane

The highly excited vibrational energy levels of Sill stretches of silane Si H4 in the electronic ground state are calculated using a three-parameter no nlinear model, i.e., the quantized discrete self-trapping equation. The obt ained results are in good agreements with the experimental data and with th ose obtained from local mode calculations of others. We note that SiH4 mole cule is a typical molecule close to the local mode limit, and that when n g reater than or equal to 3, the molecule could be thought of as vibrating wi th the four SiH stretching quanta trapped into a single SiH bond.