An Infrared and Raman Spectroscopic Study of Crystalline Trans-Crotonic Acid

Abstract

Trans-crotonic acid was studied by FT-IR and Raman spectroscopies. A detailed assignment of the vibrational spectra in the crystalline phase (where dimeric units exist) is reported and discussed in comparison with that of the monomer isolated in a low temperature argon matrix. Results of molecular orbital calculations (semiempirical AM1 and ab initio 6–31G∗) on both monomeric and dimeric trans-crotonic acid are also presented and used to help the interpretation of the spectroscopic data.