Straka Michal, Hrobárik Peter, Kaupp Martin
Institut für Anorganische Chemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany.
J Am Chem Soc. 2005 Mar 2;127(8):2591-9. doi: 10.1021/ja044982+.
The relationship between structure and bonding in actinide 6d(0)5f(0) MX(6)(q)() complexes (M = Th, Pa, U, Np; X = H, F; q = -2,-1, 0, +1) has been studied, based on density functional calculations with accurate relativistic actinide pseudopotentials. The detailed comparison of these prototype systems with their 5d(0) transition metal analogues (M = Hf, Ta, W, Re) reveals in detail how the 5f orbitals modify the structural preferences of the actinide complexes relative to the transition metal systems. Natural bond orbital analyses on the hydride complexes indicate that 5f orbital involvement in sigma-bonding favors classical structures based on the octahedron, while d orbital contributions to sigma-bonding favor symmetry lowering. The respective roles of f and d orbitals are reversed in the case of pi-bonding, as shown for the fluoride complexes.
基于使用精确相对论锕系赝势的密度泛函计算，研究了锕系6d(0)5f(0) MX(6)(q)()配合物（M = Th、Pa、U、Np；X = H、F；q = -2、-1、0、+1）中结构与键合之间的关系。将这些原型体系与其5d(0)过渡金属类似物（M = Hf、Ta、W、Re）进行详细比较，详细揭示了5f轨道相对于过渡金属体系如何改变锕系配合物的结构偏好。对氢化物配合物的自然键轨道分析表明，5f轨道参与σ键合有利于基于八面体的经典结构，而d轨道对σ键合的贡献有利于对称性降低。如氟化物配合物所示，在π键合的情况下，f和d轨道的各自作用相反。
