Molecular structure and spectral properties of 4-(1-pyridinium)-butyrate dihydrate and its hydrobromide

The molecular structure and properties of 4-(1-pyridinium)-butyric acid bromide have been characterized by X-ray diffraction, B3LYP/6-311 + +G(d,p) calculations, FTIR and Raman spectra, and compared with those of 4-(1-pyridinium)-butyrate dihydrate. The FTIR spectra show a broad absorption attributed to the νCOOH⋯Br and νCOO⋯H2O. In Raman spectra these absorptions are absent. The experimental and theoretical infrared spectra of these compounds are discussed. The vibrational spectra have been interpreted with the use of computed potential energy distribution (PED).