Zou Jinghan, Xie Hua, Yuan Qinqin, Zhang Jumei, Dai Dongxu, Fan Hongjun, Tang Zichao, Jiang Ling
State Key Laboratory of Molecular Reaction Dynamics, Collaborative Innovation Center of Chemistry for Energy and Materials (iChEM), Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, Liaoning, P. R. China.
Phys Chem Chem Phys. 2017 Apr 12;19(15):9790-9797. doi: 10.1039/c7cp00171a.
A series of heterobinuclear group 4 metal-nickel carbonyls MNi(CO) (M = Ti, Zr, Hf; n = 3-7) has been generated via a laser vaporization supersonic cluster source and characterized by mass-selected photoelectron velocity-map imaging spectroscopy. Quantum chemical calculations have been carried out to elucidate the geometric and electronic structures and support the spectral assignments. The n = 3 cluster is determined to be capable of simultaneously accommodating three different types of CO bonds (i.e., side-on-bonded, bridging, and terminal modes), resulting in a MNiη(μ-C, O)(CO) structure, which represents the smallest metal carbonyl with the involvement of all the main modes of metal-CO coordination to date. The building block of three bridging CO molecules is favored at n = 4, the structure of which persists up to n = 7. The additional CO ligands are bonded terminally to the metal atoms. The present findings provide important new insight into the structure and bonding mechanisms of CO molecules with heteronuclear transition metals, which would have important implications for understanding chemisorbed CO molecules on alloy surfaces.
通过激光蒸发超声团簇源生成了一系列第4族异双核金属 - 镍羰基化合物MNi(CO)ₙ（M = Ti、Zr、Hf；n = 3 - 7），并通过质量选择光电子速度映射成像光谱进行了表征。已进行量子化学计算以阐明其几何和电子结构，并支持光谱归属。确定n = 3的团簇能够同时容纳三种不同类型的CO键（即侧基键合、桥连和端基模式），从而形成MNi[η(μ - C,O)](μ - CO)(CO)结构，这是迄今为止涉及金属 - CO配位所有主要模式的最小金属羰基化合物。n = 4时，三个桥连CO分子的结构单元更受青睐，其结构一直持续到n = 7。额外的CO配体以端基方式与金属原子键合。本研究结果为CO分子与异核过渡金属的结构和键合机制提供了重要的新见解，这对于理解合金表面上化学吸附的CO分子具有重要意义。
