Department of Spectroscopy, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.
J Phys Chem A. 2013 Feb 21;117(7):1601-13. doi: 10.1021/jp309792v. Epub 2013 Feb 5.
Density functional theory was applied to study the interaction of group IIb transition-metal cations (Zn(2+), Cd(2+), and Hg(2+)) with one and two fully or partially deprotonated 3-mercaptopropionic acid ligands. In this investigation, we determined the geometries of all possible complexes resulting from the coordination of the metal ions with the ligands at different binding sites selected on each ligand. The relative energies of the complexes, metal-ion affinities, free energies, and entropies were also determined. The natures of the bonds were critically analyzed by natural bond orbital (NBO) analysis and clarified further using the atoms-in-molecules (AIM) approach. The substantial influence of the solvent (water) polarization on the energetics, geometries, and bonding of the molecular complexes was also investigated by the conductor-like screening solvation model (COSMO). In an attempt to simulate the complexes in an aqueous environment, water molecules were added explicitly to complete the coordination sphere of the metal cations, and the corresponding metal-ion affinities were calculated to study the effect of microhydration.
密度泛函理论被应用于研究 IIb 族过渡金属阳离子（Zn(2+)、Cd(2+)和 Hg(2+)）与一个和两个完全或部分去质子化的 3-巯基丙酸配体的相互作用。在这项研究中，我们确定了金属离子与配体在每个配体上选择的不同结合位点配位时产生的所有可能配合物的几何形状。还确定了配合物的相对能量、金属离子亲和力、自由能和熵。通过自然键轨道（NBO）分析对键的性质进行了严格分析，并使用分子中的原子（AIM）方法进一步阐明。还通过导体相似性屏蔽溶剂化模型（COSMO）研究了溶剂（水）极化对分子配合物的能量、几何形状和键合的重大影响。为了尝试在水相环境中模拟配合物，我们明确添加水分子以完成金属阳离子的配位球，并计算相应的金属离子亲和力以研究微水合的影响。
