The High Resolution Rotational Spectrum of Silylbromide, SiH3 81Br

Abstract

Abstract The microwave spectrum of SiH3 81Br has been reanalysed in the frequency range 8-40 GHz under high resolution. From 64 observed hyperfine transitions improved values for the rotational constant B = 4292646.2(4) kHz and the quadrupole coupling constant eqQ = 279825(5) kHz were obtained. Furthermore the centrifugal distortion constants DJ = 1.81(1) kHz and DJK = 29.19(4) kHz and the spin-rotation constants CN = -2.32(40) kHz and CK = -34.2(11) kHz were determined. From the values of CN and CK the 81Br nuclear shielding tensor is calculated. An improved value of ∣μ∣ - 1.319(8) D is given for the molecular electric dipole-moment.