THEORETICAL CALCULATION OF GEOMETRY AND VIBRATIONAL FREQUENCIES OF TRIPHENYLMETHANE

Abstract

The Raman spectrum of polycrystalline triphenylmethane (TPhM) is recorded at room temperature in the range 4000-400 cm^{- 1} . The optimal structure and the vibrational spectra (Raman and IR) of TFM have been calculated in the B3LYP/6-311G (d, p) approximation. On the basis of visualization of vibrations, the theoretical modes and the corresponding experimental bands of the Raman spectrum are assigned to the valence and deformation vibrations of certain bonds in the TFM molecule. Most bands and, in particular, the most intense bands in the Raman spectra of TFM are due to vibrations in monosubstituted benzene rings. Some of the theoretical modes and the corresponding experimental bands are assigned to benzene modes in Wilson notation.