DFT Study of the Tetranuclear Lutetium and Yttrium Polyhydride Cluster Complexes [(C5Me4SiMe3)4Ln4H8] (Ln = Lu, Y) that Contain a Four-Coordinate Hydrogen Atom
DFT Study of the Tetranuclear Lutetium and Yttrium Polyhydride Cluster Complexes [(C5Me4SiMe3)4Ln4H8] (Ln = Lu, Y) that Contain a Four-Coordinate Hydrogen Atom
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DOI：
10.1021/om0502382
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发表时间：
2005-08
期刊：
影响因子：
2.8
通讯作者：
Yi-dong Luo;J. Baldamus;Olivier Tardif;Z. Hou
中科院分区：
文献类型：
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作者：
Yi-dong Luo;J. Baldamus;Olivier Tardif;Z. Hou
密度泛函理论计算揭示了四核钚和钇多氢化合物[(C5Me4SiMe3)4Ln4H8](Ln=Lu，Y)的结构的一些前所未有的方面。与前面描述的(C5Me4SiMe3)4Lu4H8的X射线分析相比，(C5Me4SiMe3)4Lu4H8存在严重的无序问题，表现出一个C2v对称结构，一个体心μ4-H，两个面帽μ3-H，和五个边桥μ2-H原子，本密度泛函研究表明，优化的Ln4H8核更倾向于具有一个体心μ4-H，一个面帽μ3-H和六个边桥μ2-H原子的伪C3v对称结构。在这些配合物中还观察到了通过氢化桥的金属−金属轨道相互作用。Wiberg键指数和线性重叠键级数很好地证明了μ4-H键方式是一种新的氢键方式。(C_5Me_4SiMe_3)_4Y_4H_8的X射线结构与理论计算符合得很好。
DFT calculations revealed some unprecedented aspects of the structure of the tetranuclear lutetium and yttrium polyhydride complexes [(C5Me4SiMe3)4Ln4H8] (Ln = Lu, Y). In contrast with the previously described X-ray analysis of (C5Me4SiMe3)4Lu4H8, which suffered from a serious disorder problem and showed a C2v-symmetrical structure with one body-centered μ4-H, two face-capped μ3-H, and five edge-bridged μ2-H atoms, the present DFT studies indicated that the optimized Ln4H8 core prefers a pseudo-C3v-symmetrical structure with one body-centered μ4-H, one face-capped μ3-H, and six edge-bridged μ2-H atoms. Metal−metal orbital interactions via the hydride bridges were also observed in these complexes. The μ4-H bonding fashion, a new bonding mode for hydrogen, was well proved by the Wiberg bond indexes and linear overlap bond orders. The X-ray structure of (C5Me4SiMe3)4Y4H8, which was solved without suffering from the disorder problems, showed excellent agreement with the theoretical calculations.