STRUCTURAL ANALYSIS AND ORBITAL INTERACTIONS OF PROLINE

Abstract

In this work, proline (Pro) was studied theoretically at the Density Functional Theory (DFT) methods with B3LYP/6-311++G(d,p) level and four conformers with minimum energy were found. The calculations were done for these conformers. Electronic energies, Gibbs energies, the Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) energy values were calculated. The Natural Bond Orbital (NBO) interactions were analyzed, and plotted. Electron density surfaces of the selected NBOs for Pro conformers showing the dominant orbital interactions, calculated at the Becke3LYP/6-311++G(d,p) level, were drawn. For Pro conformers, orbital energies for NBO pairs were calculated by Fock matrix equation.

Keywords

• Amino Acid,Proline,NBO

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