School of Chemical Engineering, Inner Mongolia University of Technology, Hohhot, 010051, PR China.
J Phys Chem A. 2010 Jan 21;114(2):1218-23. doi: 10.1021/jp910326a.
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.
在高斯-3（G3）理论的最高水平上研究了中性 BeSi(n)（n=2-10）物种及其阴离子的平衡几何形状和能量。结果表明，这些团簇的基态结构是硅笼中封装的 Be，其中 n≥8。BeSi(n)的可靠绝热电子亲合势已被预测为 BeSi(2)为 1.68eV，BeSi(3)为 1.87eV，BeSi(4)为 2.33eV，BeSi(5)为 2.29eV，BeSi(6)为 2.11eV，BeSi(7)为 2.37eV，BeSi(8)为 2.95eV，BeSi(9)为 2.74eV，BeSi(10)为 1.92eV。还计算了从 BeSi(n)中脱离 Be 原子、从 BeSi(n)中脱离 Si 原子以及从 Si(n)团簇中脱离 Si 原子的离解能，以分别检验相对稳定性。BeSi(n)的稳定性趋势随 n 的变化与 n≤7 时 Si(n)的稳定性趋势相反。从 n≥8 开始，硅笼中封装的 Be 原子不仅使 BeSi(n)和 Si(n)的稳定性趋势相同，而且还提高了 Si(n)团簇的稳定性。
