Subcategory: Materials Science
Room: Exhibit Hall A
Diamond Boddie - Clark Atlanta University
Co-Author(s): Jovian Lazare, Clark Atlanta University, Atlanta, GA; Tandabany Dinadayalane*, Clark Atlanta University, Atlanta, GA
Density functional theory (DFT) calculations were performed to understand the binding of naturally occurring aliphatic amino acids (glycine, alanine, valine, leucine, isoleucine, and methionine) individually with two finite-size graphene sheets. Conformational analyses for these six amino acids were initially performed using Merck Molecular Force Field (MMFF) then the geometries of all conformers were optimized at the HF/6-31G(d) and M06-2X/6-31G(d) levels using Spartan ’18 software package. The lowest energy conformers from two distinct hydrogen bonding backbone configurations were selected at the M06-2X/6-31G(d) level. These two conformers for each of the amino acids were used to build complexes with graphene by considering different possible binding modes. All complexes were fully optimized using M06-2X/6-31G(d) level. Binding energies with and without basis set superposition error (BSSE) correction were calculated and analyzed. Our study reveals that multiple weak interactions namely, C-H…pi, N-H…pi, and/or O-H…pi interactions contribute for overall stabilization of the complexes. The data obtained from our computational study may be helpful for force field development and for future experiments on non-covalent interactions of amino acids with graphene. Our goal is to understand the relationship between the binding affinities of various complexes and structural features including the orientation of amino acid adsorbed on two different sizes of graphene sheets. The binding strengths for two different conformers having distinct hydrogen bonding have been assessed for the series of amino acids using quantum mechanical calculations.
Funder Acknowledgement(s): NSF HBCU-UP 1601071
Faculty Advisor: Dr. Tandabany Dinadayalane, email@example.com
Role: I contributed in building the complexes, running the calculations using supercomputers, checking the results, preparing the figures from the output files.