Structure Conformation, Vibrational Properties, NLO Activity, HOMO-LUMO and Thermodynamic Parameters of Dinicotinic Acid Using Experimental and Theoretical Approach

In the present study, the Dinicotinic acid was characterized by FTIR and FT-Raman spectra in the range of 4000-450 and 4000-50 cm(-1). The most stable molecular structure and optimized geometrical parameters are calculated using DFT studies. Normal Co-ordinate Analysis (NCA) was studied out by solving Inverse Vibrational Problem using 74-valence force field calculations using overlay least square technique. It reproduces into 35 fundamental frequencies with an rms error of 9.28 cm(-1) in the zero-order calculations. Based on PED, vibrational modes are assigned for this molecule. The energy of HOMO & LUMO, NLO parameters, and thermodynamic parameters were computed.