团簇Ni4P反应活性的密度泛函研究

Studies on Density-Functional Theory for Reaction Activity of NiP Cluster

为了探究团簇Ni4P反应活性最强的结构,运用密度泛函理论中的B3LYP/Lan12dz水平对团簇Ni4P进行了优化计算,得到二、四重态下6种优化构型。从最高占据分子轨道(HOMO)-最低未占分子轨道(LUMO)图、前线轨道能隙差及库普曼斯定理角度对其反应活性展开研究,结果表明,构型1(4)~2(2)得电子能力强于失电子能力,构型3(4)~3(2)失电子能力强于得电子能力;团簇Ni4P各优化构型反应活性大小关系为:2(2)<1(2)<1(4)<2(4)<3(4)=3(2),说明构型3(4)和3(2)最可能成为非晶态合金Ni4P催化剂的有效结构。

In order to investigate the most active structure of Ni4P cluster, the density functional theory was used to optimize and calculate the Ni4P cluster at B3 LYP/Lanl2 dz level, and six kinds of optimized configurations were obtained in the binary and quadruple states. The reaction activity was examined from highest occupied molecular orbital(HOMO)-lowest unioccupied molecular orbital(LUMO) orbital diagram, frontier orbital energy gap and the Kupmans theorem. The results showed that configurations of 1(4)~2(2) accept electrons are stronger than give electrons, but configurations of 3(4)~3(2) give electrons are stronger than accept electrons. The relationship between the reaction activity of optimized configurations of Ni4P cluster are 2(2)<1(2)<1(4)<2(4)<3(4)=3(2). It is proved that configurations 3(4) and 3(2) are the most likely effective structures for amorphous Ni4P alloy catalyst.