Far infrared and microwave spectral studies on the molecular dynamics and interactions of methyl iodide in carbon disulphide solution

Abstract

The far-infrared and microwave spectra of methyl iodide in dilute solution (0.1 mf) in carbon disulphide have been used to measure the relaxation times and correlation function for dipole reorientation in this particular medium. It is shown that rotation is faster than in the liquid phase due to removal of intermolecular correlations. The short time part of the correlation function is shown to be distinctly non-exponential and this part of the power spectrum is fitted to a model which enables the intermolecular mean square torque to be determined. The spectral second moment agrees well with that calculated using the classical rotational energy indicating that induced dipole absorption is not of major importance in this solution.