The spectra and structure of sulphur-containing organic compounds-II. The vibrational spectra and internal rotation of dimethylsulphate

Abstract

An investigation of the i.r. spectra of (CH3O)2SO2 in liquid and crystalline states has been carried out. The crystals were obtained by freezing the liquid and precipitating the vapour on a cooled KBr plate. Four crystalline modifications have been obtained. The i.r. spectra of oriented crystalline films have been investigated in polarized light. A normal coordinate analysis has been carried out, an interpretation of the spectrum given and the force field determined. It has been shown on the basis of experimental data and theoretical analysis that there is an equilibrium of three rotational isomers in (CH3O)2SO2 in the liquid and solutions. Different numbers of conformers have been found in different crystalline modifications. © 1979.