Attila Kovács, Vladislav Izvekov, Gábor Keresztury, Gábor Pongor

Vibrational analysis of 2-nitrophenol.

A joint FT-IR, FT-Raman and scaled quantum mechanical study.

Chemical Physics, 238 (1998) 231-243

FT-IR (gas, solution, solid) and FT-Raman (solution, solid) spectra of 2-nitrophenol have been recorded in the range of 4000-30 cm^-1. The spectra were interpreted with the aid of normal coordinate analysis based on a scaled Becke3-Lee-Yang-Parr/6-31G* density functional force field utilising a set of scale factors introduced recently by Rauhut and Pulay (G. Rauhut and P. Pulay, J. Phys. Chem., 1995, 99, 3093). These scale factors, developed on a small training set of organic molecules containing no hydrogen bonding moieties, were found to be well transferable to 2-nitrophenol including the strong intramolecular (O)H^...O(N) hydrogen bonding moiety as well. The scaled force field reproduced the experimental frequencies of the molecule by a weighted mean deviation of 10.5 cm^-1. Based on the calculated results, 38 fundamentals from a total of 39 were identified and assigned, revising the assignments of earlier experimental studies for several fundamentals.

FT-IR and computed (scaled) IR spectra of 2-nitrophenol (0.1 M CCl₄ solution). () indicates a range of strong solvent absorption.