Infrared and raman spectra, vibrational assignment and barriers to internal rotation for methyldisilylamine

Abstract

The Raman spectra of gaseous and liquid (SiH 3) 2NCH 3 and (SiH 3) 2NCD 3 have been recorded to within 10 cm −1 of the exciting line. The IR spectra of (SiH 3) 2NCH 3 and (SiH 3) 2NCD 3 have been recorded from 80 cm −1 to 3800 cm −1 in the gaseous state, and from 80 cm −1 to 450 cm −1 in the solid state. A vibrational assignment has been made, and from the low-frequency vibrational data, an upper limit of 3.3 kcal mol −1 was calculated for the barrier to internal rotation of the silyi groups, whereas a barrier of ~450 cal was calculated for internal rotation of the methyl group. It is concluded that there exists a significantly strong d π— p π interaction in methyldisilylamine.