Vibrational spectroscopic investigation (FT-IR and FT-Raman) on 1,2-dibromobenzene by HF and hybrid (LSDA and B3LYP) calculations

► The FT-IR and FT-Raman spectra of 1,2-dibromobenzene have been recorded in the region 4000-100 cm−1. ► The vibrational frequencies have been computed theoretically using HF and DFT level of theory (B3LYP and LSDA). ► The geometrical structure of the compound is fractured by the substitutions of couple of Br in the ring. ► From the vibrational assignments it is observed that, the vibrational pattern of the fundamental modes is realigned slightly with respect to the substitutions.