第一性原理比较研究M_nP_m(M=Al,Ga,In,2≤n+m≤3)团簇(英文)  

First principles comparative study of polyatomic clusters of M_nP_m(M=Al,Ga,and In,2 ≤ n+m ≤ 3 )

作　　者：张文庆[1] 高银浩[1] 姚树文[1] 

机构地区：[1]河南科技学院,新乡453003

出　　处：《原子与分子物理学报》2009年第2期283-289,共7页Journal of Atomic and Molecular Physics

摘　　要：利用密度泛函理论对M_nP_m(M=A1,Ga,and In,2≤n+m≤3)团簇的几何和电子结构性质及稳定性进行了研究.结果表明,三原子的M_nP_m团簇是二重态,而单体则是三重态.富P的MP_2团簇是具有C_(2V)对称性的等腰三角形结构,而富M的M_2P团簇则是具有C_s对称性的三角形结构.在三原子磷化物团簇中,MP_2团簇比M_2P团簇稳定,而后者中M-P键的强度比前者强.对于这些小的磷化物团簇,电离势高于裂解能,表明裂解比电离占优势.Ga_2P比Al_2P和In_2P的HOMO-LUMO能隙和电离势都高,归咎于在富金属的M_2P团簇中,相对较强的Ga-P键.The structural,electronic properties,and stability of M_n P_m(M=Al,Ga,and In,2≤n+m≤3 )clusters have been investigated by density-functional theory.The results indicate that triatomic isomers prefer doublet spin states,whereas triplets are predicted for the monomer.The lowest energy structures of phosphorus-excess triatomic clusters are an isoceles triangle with C_(2V)symmetry,and metal-excess triatomic clusters show minimum energy configurations to be a triangle with C_s symmetry.In the triatomic clusters,MP_2 clusters are more stable than M_2 P clusters,while the Metal-P bond in the latter is stronger than that in the farmer.The calculated ionization potentials are larger than the fragmentation energies of these small phosphide clusters,exhibiting a dominance of dissociate over ionization.For M_2 P clusters,the HOMO-LUMO gap and ionization potential values of Ga_2P are higher than those of Al_2P and In_2P,due to the relatively strong Ga-P bond in the metal-excess M_2P clusters.

关 键 词：磷化物团簇 几何结构与电子性质 稳定性 密度泛函理论 

分 类 号：O561.1[理学—原子与分子物理]