The effect of the substitution site on the macroscopic and spectroscopic properties of bromo-substituted benzophenones

Abstract

The influence of the bromine position in the phenyl ring on the macroscopic and vibrational properties of bromo-substituted benzophenones was studied using spectroscopic and differential scanning calorimetry methods. Specifically, we investigated FT-IR, FT-Raman, low-frequency Raman spectra, and melting temperatures of the three isomers of bromo-substituted benzophenones differing in the position of the Br atom in one of the phenyl rings. It was found, that an increase in the distance of the bromine atom relative to the carbonyl group C ˭ O in the phenyl ring leads to an increase in the melting point, a decrease in the stretching vibrations frequency Q(C˭O) in FT-IR and FT-Raman spectra, as well as to a shift in the lattice vibrations frequency to the low-frequency side relative to the corresponding vibration in pure benzophenone.