非晶态原子团簇Co_nP_m^+、Ni_nP_m^+的生成与结构分析

Non Crystal Clusters Co nP + m and Ni nP + m: Generation and Structure Analysis

应用量子化学从头计算方法研究了激光等离子体反应生成的非晶团簇ＣｏｎＰ＋ｍ、ＮｉｎＰ＋ｍ．考查和分析了可能的几何构型及稳定性．ＣｏｎＰ＋ｍ有两条生长螺线：１）从ｍ＝４到ｍ＝８，构型变化为四边形→三角双锥→畸变八面体→双四面体；２）从ｍ＝７到ｍ＝１１，构型变化为三棱柱加帽→长方体→四棱柱加帽→五棱柱，其中Ｃｏ嵌在多面体中．ＮｉＰ＋ｍ只有一条生长螺线ＮｉＰ＋７～ＮｉＰ＋１１，Ｐｍ形成网络，Ｎｉ仅与其中部分Ｐ原子成键．

Non crystal clusters Co nP + m and Ni nP + m , which were generated by laser plasma reaction, have been studied by using quantum chemistry ab initio method. Possible geometry structures are examined and optimized. There are two growing helices for Co nP + m : (1) From m=4 to m=8, the geometric structure develops following square→trigon bipyramid→distorted octahedron→bi tetrahedron; (2) From m=7 to m=11 the configuration develops from capped trigon prism, quadratic prism, capped quadratic prism to pentagon prism, where Co is embedded on the polyhedron. There is only one growing helix for Ni nP + m with m going from 7 to 11. P atoms forms a net, and Ni is only bonded to some of the atoms.