title: Conformational analysis of alkali metal complexes of anionic species of aspartic acid, their interconversion and deprotonation: a DFT investigation.
abstract: Gas-phase geometry-optimized structures of aspartate complexes of anionic species (Hasp(-)) with lithium, sodium and potassium metal cations and transition-state structures for their interconversions were obtained using the density functional theory computations at the B3LYP/6-311++G(d,p) level of theory. The metal ion affinities of Hasp(-) species and deprotonation energies of [Hasp-M] complexes, M=Li+, Na+ and K+, and their conformers were obtained. Relative energies of the [Hasp-M] complex conformers, reaction energies, thermodynamic properties, rate and equilibrium constants of their complexation are reported. Binding energies of the most stable complexes with Li+, Na+ and K+ are -168.53, -133.34 and -117.68kcal/mol, respectively. The most stable complex conformer as a tri-coordinated form for aspartate complex with Li(+) and bi-coordinated form for aspartate complexes with Na+ and K+ were found.
authors: Supramolecular Chemistry Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors: Wichien
authors: W
authors: Sang-Aroon
authors: Vithaya
authors: V
authors: Ruangpornvisuti
mesh_terms: D000838:Anions; D001224:Aspartic Acid / Q000737:chemistry*; D019295:Computational Biology / Q000379:methods*; D005740:Gases; D008024:Ligands; D008094:Lithium / Q000737:chemistry; D008672:Metals, Alkali / Q000737:chemistry*; D008968:Molecular Conformation; D011188:Potassium / Q000737:chemistry; D011522:Protons; D012964:Sodium / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D000838:Anions; D005740:Gases; D008024:Ligands; D008672:Metals, Alkali; D011522:Protons; D001224:Aspartic Acid; D008094:Lithium; D012964:Sodium; D011188:Potassium