Department of Physics, Southeast University, Nanjing, 211189, People's Republic of China.
J Phys Chem A. 2010 Sep 2;114(34):9398-403. doi: 10.1021/jp106129r.
We have systematically investigated mixed inorganic/organic ligand sandwich clusters comprised of 3d transition metal (TM) atoms with C(60) and benzene (Bz) molecules, BzTMC(60), by using all electron density functional theory. We found the bonding type between TM and C(60) in the ground state evolves from eta(6) (TM = Sc-Cr) to eta(5) (TM = Mn) and then to eta(2) (TM = Fe, Co) with increasing number of d electrons of TM. The BzTMC(60) clusters (TM = Sc-Co) are of high stability through ionic-covalent interactions. The BzCrC(60) cluster has the lowest binding energy due to its largest spin-flip energy and the weakest ionic bonding interaction between the CrBz unit and C(60). With the exception of BzTiC(60) being triplet, all the BzTMC(60) clusters energetically prefer the lowest available spin states, e.g., the ground spin state is either a singlet (with an even number of electrons) or a doublet (with an odd number of electrons). Moreover, the magnetic properties of BzTMC(60) show clear dependence to the bond type between TM and C(60), and the eta(5)-ligand configurations tend to be in high spin states.
我们系统地研究了由 3d 过渡金属 (TM) 原子与 C(60) 和苯 (Bz) 分子组成的混合无机/有机配体夹心簇，BzTMC(60)，使用全电子密度泛函理论。我们发现，在基态下，TM 与 C(60) 之间的键合类型从 eta(6) (TM = Sc-Cr) 演变为 eta(5) (TM = Mn)，然后演变为 eta(2) (TM = Fe, Co)，随着 TM 的 d 电子数的增加。BzTMC(60)簇 (TM = Sc-Co) 通过离子-共价相互作用具有很高的稳定性。BzCrC(60) 簇由于其最大的自旋翻转能和 CrBz 单元与 C(60)之间最弱的离子键相互作用，具有最低的结合能。除了 BzTiC(60) 是三重态外，所有的 BzTMC(60) 簇都优先选择最低可用的自旋态，例如，基态是单重态 (电子数为偶数) 或双重态 (电子数为奇数)。此外，BzTMC(60) 的磁性性质明显依赖于 TM 与 C(60) 之间的键类型，eta(5)-配体构型倾向于高自旋态。
