The rotational spectrum of chlorodimethylsilane using Fourier transform microwave spectroscopy

The microwave spectra of five isotopic species of chlorodimethylsilane have been investigated in the region from 5 to 20 GHz using a Fourier Transform microwave spectrometer. The molecular structure of (CH3)(2)SiHCl obtained by the substitution method is the following one: r(s)(Si-Cl) = 2.0603(10) Angstrom, r(S)(Si-C) = 1.8542(10) Angstrom, angle ClSiC = 108.43(20)degrees, and angle CSiC = 112.32(15)degrees. The quadrupole coupling constants in the principal axis system of (CH3)(2)SiHCl have been determined to be chi (aa) = - 32.456(5) MHz, chi (bb) = 18.061(8) MHz, and chi (cc) = 14.395(8) MHz. These values are consistent with chi (aa) = - 35.556(6) MHz and eta = 0.016(10). The estimated value of the potential barrier V-3 of internal rotation of two methyl tops is in agreement with those of the related molecules. (C) 2001 Elsevier Science B.V. All rights reserved.