Electronic states of metalloid-clusters in solids

Metalloid elements such as boron and silicon form clusters in metal matrix.They show dimers，chains,2d -layers等. depending upon their hosts and compositions. Boron is especially interesting becausethe small atomic radiusi.e., 80pm. For example, B forms 2d layers in MgB D22 - D2, TiB D22 - D2, AlB D22 - D2；他们是困难的，3d结构可以在CaB6和LaB6 in CaB6和LaB6 in refractory and exhibit high electrical conductivitywhich B - D26 D2 octahedron and metal atoms form CsCl type structure. B - D212 D2 cluster can befound in YB D212 D2 and AlB D212 D2. in spite of the usefulness of these metalloids clusters，electronic states has not been clarified except for some special compounds.In the present study，系统研究：第一原则molecular orbital calculation of these systems hasbeen made in order to understand their bonding mechanisms as well as electronic mechanisms behindsmacroscopic properties of these compounds。

Metalloid elements such as boron and silicon form clusters in metal matrix.They show dimers, chains, 2D-layers etc. depending upon their hosts and compositions. Boron is especially interesting because of its small atomic radius; i.e., 80pm. For example, B forms 2D layers in MgBィイD22ィエD2, TiBィイD22ィエD2, AlBィイD22ィエD2; They are hard, refractory and exhibit high electrical conductivity.3D structures can be found in CaB6 and LaB6 in which BィイD26ィエD2 octahedron and metal atoms form CsCl type structure. BィイD212ィエD2 cluster can be found in YBィイD212ィエD2 and AlBィイD212ィエD2.In spite of the usefulness of these metalloids clusters, its electronic states has not been clarified except for some special compounds.In the present study, systematic investigation by first principles molecular orbital calculation of these systems has been made in order to understand their bonding mechanisms as well as electronic mechanisms behinds macroscopic properties of these compounds.