密度泛函理论研究Run和RunAu(n=1-12)团簇的结构和电子性质

采用密度泛函理论中的广义梯度近似(GGA) 对 Ru_n Au和Ru_n 团簇的几何构型进行优化,并对能量、频率、电子性质和磁性质进行了计算. 结果表明,Ru_n Au团簇的最低能量结构可以通过Au原子代替Ru_n+1团簇中的Ru原子生长而成.除了局域的结构畸变,Ru_n Au和Ru_n+1团簇具有相似的几何结构.二阶能量差分、电离势、亲和势和分裂能表明Ru₅, Ru₈, Ru₅Au, Ru₈Au 是稳定的团簇,Au的掺杂没有改变Ru_n 的相对稳定性.通过电子性质的分析发现,当Au原子掺杂在Ru_n 中,团簇的化学活性增加,且团簇的能隙主要由电子的配对效应决定;对于大多数团簇来说,Au原子掺杂提高了Ru_n Au的磁矩. 关键词： n Au和Ru_n 团簇')" href="#">Ru_n Au和Ru_n 团簇 几何结构 电子性质

The study on structures and properties of Ru_n and Ru_n Au(n=1—12) clusters by density functional theory

The geometries, the stabilities, and the electronic properties of Ru_n Au and Ru_n (n=1—12) clusters are systematically investigated by the density functional theory. The results suggest that the lowest energy structures for Ru_n Au clusters can be obtained by substituting one Ru atom in Ru_n+1 clusters with Au atom. The geometries of Ru_n Au clusters are similar to those of Ru_n+1 clusters except local structural distortions. The second-order difference and fragmentation energy show that Ru₅, Ru₈, Ru₅Au, and Ru₈Au clusters are the most stable among these studied clusters, the doped Au atoms do not change the relative stabilities of Ru_n clusters; the Au impurities increase the chemical activities of Ru_n clusters, and the value of gap is determined mainly by the electron-pairing effect; the doped Au atoms increase the total magnetic moments of Ru_n Au in most cases.