Structural and Vibrational Spectroscopic Analysis of Anticancer Drug Mitotane Using Density Functional Theory

A comprehensive screening of the more recent DFT theoretical approach to structural analysis is presented in this section. DFT calculations using B3LYP method and 6-311++G(d,p) as basis set were found to yield results that are comparable to experimental IR and Raman spectra. Computed geometrical parameters and frequencies of the fundamentals were found in satisfactory agreement with the experimental data and also its parent structure. The vibrational assignments of the normal modes were performed on the basis of the PED calculations using the VEDA 4 program. It can be proven from the comparative results of mitotane and its parent structure, the intramolecular nonbonding interaction between (C13-Cl18..H19) in the ortho position which is calculated 2.583 Å and the position of the substitution take over the vibrational wavenumber to redshift of 47 cm-1. In addition, natural bond orbital analysis reveals that charge delocalization throughout the molecule. Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis were investigated using theoretical calculations.