Molecular constants of SiH3C ≡ CH and SiD3C ≡ CH

A normal co-ordinate analysis of silylacetylene and silylacetylene-d₃ has been carried out following Wilson'sF-G matrix method. The potential energy constants obtained therefrom have been used to evaluate rotational distortion constants and mean square amplitudes of vibration for these molecules. Thermodynamic functions, such as heat content, free energy, entropy heat capacity for the ideal gaseous state at one atmosphere pressure and with the usual rigid rotor harmonic oscillator approximation, have also been calculated for 12 temperatures from 100°K to 1000°K.