Observed and calculated vibrational spectrum of trans-tetrachlorobispyridinesilicon(IV) and related species
Abstract
Raman spectroscopic studies on SnCl4,2NMe3 and SnCl4,2N(CD3)3 are used to define a ‘tin–nitrogen stretching vibration.’ By applying the force constant obtained for the Sn–N bond to SiCl4,2py and PCl5,py (py = pyridine) computed data are compared with the observed Raman and i.r. spectra. From vibrational data alone it is not possible to assign cis- or trans-stereochemistry to the adduct SiCl4,2py. The species SiCl3+,3py and SiCl22+,4py are examined spectroscopically and assignments of stereochemistry are proposed. The compound SiH2I2,4py is examined spectroscopically and a 1 : 3 adduct of SiCl3I with pyridine is characterised. Previous assignments on Sil4,4py, PPh5, and PCl4+,2py are criticised.