Structures and Electronic Properties of Beryllium Atom Encapsulated in Si_<i>n</i>^(0,−1) (<i>n</i> = 2−10) Clusters

Abstract

The equilibrium geometries and energies of neutral BeSi(n) (n = 2-10) species and their anions have been studied at the highest level of Gaussian-3 (G3) theory. The results reveal that the ground-state structures of these clusters are Be-encapsulated in silicon cages with n >or= 8. The reliable adiabatic electron affinities of BeSi(n) have been predicted to be 1.68 eV for BeSi(2), 1.87 eV for BeSi(3), 2.33 eV for BeSi(4), 2.29 eV for BeSi(5), 2.11 eV for BeSi(6), 2.37 eV for BeSi(7), 2.95 eV for BeSi(8), 2.74 eV for BeSi(9), and 1.92 eV for BeSi(10). The dissociation energies of Be atom from BeSi(n), Si atom from BeSi(n), and Si atom from Si(n) clusters have also been calculated, respectively, to examine relative stabilities. The trend of stability of BeSi(n) changed with n is converse to that of Si(n) when n <or= 7. From n >or= 8, the encapsulated Be atom in silicon cages not only results in an identical trend for stability of BeSi(n) and Si(n) but also improves the stability of Si(n) clusters.