Vibrational assignment of the Raman active modes of 1,10-phenanthroline-5,6-dione using DFT calculations

A complete assignment of the Raman active modes of 1,10-phenanthroline-5,6-dione in the 100-4000 cm(-1) spectral region is reported. Intense well resolved spectra of solid phendione with high S/N are reported. Assignment of the normal modes with appropriate symmetry representation symbols was achieved by employing density functional theory calculations. Our calculations were modeled on results previously reported for phenanthroline. Results of the B3LYP calculations were consistent and established that phendione possess sixty fundamentals.