Vibrational spectra and structure of isopropylbenzene

Abstract

Infrared spectra (4000-400 cm-1) and Raman spectra (1700-40 cm-1) of the liquid and two crystalline solids of isopropylbenzene (cumene) and isopropylbenzene-d12 have been recorded. The spectra indicate that in the liquid and crystalline solids isopropylbenzene exists in planar conformation only (C{single bond}H bond is in the plane of the benzene ring). An assignment of the observed band wave numbers both isopropylbenzene and isopropylbenzene-d12 is discussed by comparison with normal mode wave numbers and IR intensities calculated from ab initio 6-31G (d) force fields. © 2008 Elsevier B.V. All rights reserved.