密度泛函理论研究Be_nNa(n=2~14)团簇的结构及其电子性质(英文)

Structure and electronic properties of Ben_Na (n=2～14) cluster from density-functional theory

基于密度泛函理论研究了BenNa（n=2～14）团簇的最低能量结构及其电子性质，具体采用的计算方法是B3LYP／6—311G（d）．对于每一尺寸的团簇，我们从多个可能构型出发来寻找其最低能量结构．计算结果表明：钠原子易于附着在铍团簇的表面；Be4Na和Be9Na均具有较高的平均结合能及能隙，n=4，9是团簇的幻数；在所有的BenNa（n=2～14）团簇中，钠原子均失去电子；随着团簇尺寸n的增大，团簇内部原子间的相互作用是其价键和金属键共存．

The lowest-energy structures and electronic properties of BenNa（ n = 2-14） clusters were studied by using density-functional theory （DFT） at B3LYP/6-311G （d） level. The equilibrium geometries of Ben Na clusters with size up to n = 14 were determined from a number of possible structural isomers at each size. Our results indicate that Na prefers to be on the periphery of Be clusters. Both Be4Na and Be9Na clusters were found to be particularly stable with higher binding energy and larger electronic gap. For all the BenNa clusters studied, we found charge transfers from Na to Be site and co-existence of covalent and metallic bonding characteristics.