STRUCTURE AND BONDING OF THE TRANSITION-METAL METHYL AND PHENYL COMPOUNDS MCH(3) AND MC(6)H(5) (M=CU,AG,AU) AND M(CH3)(2) AND M(C6H5)(2) (M=ZN,CD,HG)(1)
STRUCTURE AND BONDING OF THE TRANSITION-METAL METHYL AND PHENYL COMPOUNDS MCH(3) AND MC(6)H(5) (M=CU,AG,AU) AND M(CH3)(2) AND M(C6H5)(2) (M=ZN,CD,HG)(1)
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DOI：
10.1021/om00009a032
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发表时间：
1995-09-01
期刊：
影响因子：
2.8
通讯作者：
FRENKING, G
中科院分区：
文献类型：
--
作者：
ANTES, I;FRENKING, G
用相对论赝势和大价基组量子力学方法计算了MCH(3)和MC(6)H(5)(M=Cu，Ag，Au)和M(CH3)(2)和M(C6H5)(2)(M=Zn，Cd，Hg)的几何构型和金属-碳键的解离能.在mp2水平上计算的铜-CH3键长(1.866埃)比大多数以前的研究预测的要短得多。这是由于相对论效应，而相对论效应对于准确计算铜化合物的几何构型很重要。计算出的Ag-C(苯基)键长(2.091埃)比Lingnau和Strahle(Angew)报告的所谓的银芳基络合物的实验值(1.902埃)长得多。Int.Chem.，Int.艾德恩格尔1988、27、436)。其他理论键长与实验值符合得很好。测得的化合物似乎不太可能是银芳基络合物。在CCSD(T)下计算的金属-碳离解能略低于实验值。计算结果表明，第11族甲基和苯基化合物的M-C键强度顺序为Au&Gt；Cu&Gt；Ag，而第12族元素的M-C键强度顺序为Zn&Gt；Cd&Gt；Hg。NBO方法和电子密度分布的拓扑分析表明，金属-碳键向碳端强烈极化。M-C极化从第一过渡金属排到第二和第三过渡金属排逐渐减小。NBO分析表明M(CH3)(2)和M(C6H5)(2)化合物只有一个M-C键。后一类化合物的M-C键明显比第11族甲基和苯基化合物更具离子性质。
Quantum mechanical calculations of the geometries and metal-carbon bond dissociation energies using relativistic pseudopotentials with large valence basis sets for the metals are reported for MCH(3) and MC(6)H(5) (M = Cu, Ag, Au) and for M(CH3)(2) and M(C6H5)(2) (M = Zn, Cd, Hg). The Cu-CH3 bond length calculated at the MP2 level is significantly shorter (1.866 Angstrom) than predicted in most previous studies. This is due to relativistic effects, which are important for accurate calculations of the geometries of copper compounds. The calculated Ag-C(phenyl) bond length (2.091 Angstrom) is much longer than the experimental value of the alleged silver aryl complex (1.902 Angstrom) reported by Lingnau and Strahle (Angew. Chem., Int. Ed. Engl. 1988, 27, 436). The other theoretical bond lengths are in excellent agreement with experimental values. It seems unlikely that the measured compound is a silver aryl complex. The calculated metal-carbon dissociation energies at CCSD(T) are slightly lower than the experimental values. The calculations predict that the M-C bond strengths of the group 11 methyl and phenyl compounds have the order Au > Cu > Ag, while the group 12 elements have the order Zn > Cd > Hg. The NBO method and the topological analysis of the electron density distribution show that the metal-carbon bonds are strongly polarized toward the carbon ends. The M-C polarization decreases from the first to the second and third transition metal rows. The NBO analysis gives only one M-C bond for the M(CH3)(2) and M(C6H5)(2) compounds. The M-C bonds of the latter compounds are clearly more ionic than the group 11 methyl and phenyl compounds.