Effect of electron-donor properties of substituents and solvents on vibrational spectra of p-nitrobenzenes

1. We analyzed the changes in the frequencies and integral intensities of the νsNO2 vibrations in the IR spectra of some nitrophenol, nitrothiophenol, and nitroaniline derivatives. An explanation was proposed for the reasons of the doublet structure of νsNO2, which appears in the spectra of many nitro compounds. 2. A relation was shown to exist between the spectral changes and the donor properties of the substituents or solvents.