Teixeira Filipe, Mosquera Ricardo A, Melo André, Freire Cristina, Cordeiro M Natália D S
REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , Rua do Campo Alegre, 4169-007 Porto, Portugal.
J Phys Chem A. 2014 Nov 13;118(45):10788-96. doi: 10.1021/jp506206b. Epub 2014 Nov 3.
The consequences of anchoring Mn(salen) catalysts onto a supporting material using one of the vacant positions of the metal center are tackled by studying several Mn(salen) complexes with different axial ligands attached. This is accomplished using Density Functional Theory at the X3LYP/Triple-ζ level of theory and the Atom In Molecules formalism. The results suggest that both Mn(salen) complexes and their oxo derivatives should lie in a triplet ground state. Also, the choice of the axial ligand bears a moderate effect on the energy involved in the oxidation of the former to oxo-Mn(salen) complexes, as well as in the stability of such complexes toward ligand removal by HCl. AIM analysis further suggests that the salen ligand acts as a "charge reservoir" for the metal center, with strong correlations being obtained between the charge of salen and the electron population donated by the axial ligand to the metal center. Moreover, the results suggest that the Mn atom in Mn(salen) complexes holds different hybridization of its valence orbitals depending on the type of axial ligand present in the system.
通过研究几种带有不同轴向配体的Mn(salen)配合物，探讨了利用金属中心的一个空位将Mn(salen)催化剂锚定在载体材料上的后果。这是在X3LYP/三重ζ理论水平和分子中的原子形式体系下，使用密度泛函理论完成的。结果表明，Mn(salen)配合物及其氧代衍生物都应处于三重基态。此外，轴向配体的选择对前者氧化为氧代-Mn(salen)配合物所涉及的能量，以及此类配合物对HCl去除配体的稳定性有适度影响。AIM分析进一步表明，salen配体充当金属中心的“电荷库”，salen的电荷与轴向配体向金属中心提供的电子数之间存在很强的相关性。此外，结果表明，Mn(salen)配合物中的Mn原子根据体系中存在的轴向配体类型，其价轨道具有不同的杂化形式。
