Wichien Sang-aroonVithaya RuangpornvisutiMahidol University2018-08-242018-08-242007-07-01Journal of Molecular Graphics and Modelling. Vol.26, No.1 (2007), 342-351109332632-s2.0-34250851726https://repository.li.mahidol.ac.th/handle/123456789/24345The gas-phase geometry optimizations of mono and dinuclear complexes of dianionic species of aspartic acid, asp2-with lithium, sodium and potassium cations were carried out using density functional calculation at the B3LYP/6-311++G(d,p) level. The metal ion affinities (MIAs) of asp2-species and its complexes [asp-M]-, M = Li+, Na+and K+were determined using the vibrational frequency calculations at the same level of theory. The most stable complex conformer for aspartate complexes with Li+, Na+and K+alkali cations were found as a tri-coordinated form. All complexations of [asp-M]-and [asp-M2] complexes were found to be exothermic reactions. Relative bond distances between the alkali metal cation M+and the binding atoms of aspartate ion in [asp-M]-and [asp-M2] complexes are in decreasing order: K+> Na+> Li+. © 2007.Mahidol UniversityChemistryComputer ScienceMaterials ScienceArticleSCOPUS10.1016/j.jmgm.2007.01.001