Density functional study and the vibrational spectra of 4-chloro-5-fluoro-1,2-phenylenediamine

The solid phase FTIR and FT-Raman spectra of 4-chloro-5-fluoro-1,2-phenylenediamine (C6H6ClFN2) have been recorded in the region 4000-400 and 3500-100 cm−1, respectively. The spectra were interpreted with the aid of normal coordinate analysis following a full structure optimization and force field calculations based on the density functional theory (DFT) using the standard B3LYP/6-31G∗ method and basis set combination. A close agreement was achieved between the observed and calculated frequencies by refinement of the scale factors.