2.2 Running quantum mechanical calculations:
The most stable conformations of all the modifications were taken for
quantum calculations. Full geometry optimization and frequency
calculations were done on these structures using density functional
theory (DFT) method using the B3LYP/6-31G(d,p) basis
set45 in the gas phase. Again, the DFT single point
calculations were carried out using B3LYP/6-311G(d,p) basis
set46,47 for the most stable conformations of all the
modifications by adding water as a solvent using polarizable continuum
solvation model of Gaussian. For the optimization and frequency
calculations Gaussian0348 was used and for single
point calculation with solvent models, Gaussian0949was used. Gausssum50 was used for the generation of
DOS spectrum, IR spectrum plots.