Shao Xuecheng, Qu Xin, Liu Siyu, Yang Lihua, Yang Jinghai, Liu Xiaohui, Zhong Xin, Sun Shuai, Vaitheeswaran G, Lv Jian
State Key Laboratory for Superhard Materials, College of Physics, Jilin University Changchun 130012 China
College of Materials Science and Engineering, Jilin University Changchun 130012 China.
RSC Adv. 2019 Jan 23;9(5):2870-2876. doi: 10.1039/c8ra09143a. eCollection 2019 Jan 18.
The electron-deficient nature of boron endows isolated boron clusters with a variety of interesting structural and bonding properties that can be further enriched through metal doping. In the current work, we report the structural and electronic properties of a series of chromium-doped boron clusters. The global minimum structures for CrB clusters with an even number of ranging from 8 to 22 are proposed through extensive first-principles swarm-intelligence structure searches. Half-sandwich structures are found to be preferred for CrB, CrB, CrB and CrB clusters and to transform to a drum-like structure at CrB cluster. Endohedral cage structures with the Cr atom located at the center are energetically most favorable for CrB and CrB clusters. Notably, the endohedral CrB cage has a high symmetry of and a large HOMO-LUMO gap of 4.38 eV, whose stability is attributed to geometric fit and formation of an 18-electron closed-shell configuration. The current results advance our understanding of the structure and bonding of metal-doped boron clusters.
硼的缺电子性质赋予孤立的硼簇各种有趣的结构和键合特性，通过金属掺杂可进一步丰富这些特性。在当前工作中，我们报道了一系列铬掺杂硼簇的结构和电子性质。通过广泛的第一性原理群体智能结构搜索，提出了偶数个从8到22的CrB簇的全局最小结构。发现半夹心结构对于CrB、CrB、CrB和CrB簇是优选的，并且在CrB簇处转变为鼓状结构。Cr原子位于中心的内包层笼状结构对于CrB和CrB簇在能量上最有利。值得注意的是，内包层CrB笼具有高对称性的 以及4.38 eV的大的HOMO-LUMO能隙，其稳定性归因于几何拟合和18电子闭壳层构型的形成。当前结果推进了我们对金属掺杂硼簇的结构和键合的理解。
