The anharmonic force constant K234 of CH 3CN in different phases, solvents and complexes with Lewis acids

Abstract

The Fermi coupling coefficient W and the anharmonic force constant K 234 of CH 3CN have been determined from i.r. and Raman studies of the v 2— v 3+ v 4 Fermi doublet in liquid and gaseous phases, solutions in inert, basic and acidic solvents and in crystalline complexes with Lewis acids. The values of these parameters have been calculated by a modification of the Winther method. This method is also applied to gas phase data of the isotopic speices 13CH 3CN, CH 3 13CN and CH 3C 15N. Values of W are approximately 13±1 cm −1 except for basic and inert solvents where they are approximately 18 cm −1.