Lin Lin, Yang Jucai
College of Science, Inner Mongolia University of Technology, Hohhot, 010051, People's Republic of China.
J Mol Model. 2015 Jun;21(6):155. doi: 10.1007/s00894-015-2702-5. Epub 2015 May 24.
The structures and energies of copper-doped small silicon clusters CuSi n (n = 4-10) and their anions were investigated systematically using CCSD(T)/aug-cc-pVTZ-DK//MP2/6-31G(2df,p), G4//MP2/6-31G(2df,p), and the B3LYP/6-311+G* basis set. The performance of the methods used for the prediction of energetic and thermodynamic properties was evaluated. Comparing experimental [Xu et al. (2012) J Chem Phys 136:104308] and theoretical calculations, it was concluded that the CCSD(T) results are very accurate and exhibit the best performance; the mean absolute deviation from experimental data was 0.043 eV. The excellent agreement of vertical detachment energy (VDE) between experimental results and CCSD(T) calculations indicates that the ground state structures of CuSi n (-) (n = 4-10) presented in this paper are reliable. For CuSi10, assigning 2.90±0.08 eV to the experimental adiabatic electron affinity (AEA) and 3.90±0.08 eV to the VDE is more reasonable than to 3.46±0.08 eV and 3.62±0.08 eV, respectively, based on the CCSD(T) calculations and the previous photoelectron spectrum of CuSi10 (-) (Xu et al., op. cit.). The AEAs of CuSi n (n = 4-10), excluding CuSi7, are in excellent agreement with experimental data, showing that the ground state structures of CuSi n (n = 4-6, 8-10) reported in this paper are reliable. CuSi10 is suggested to be the smallest endohedral ground state structure. However, adding an additional electron to CuSi10 pulls out the Cu atom from the center location, forming an exohedral ground state structure of CuSi10 (-). The charge transfer and dissociation energy of Cu from CuSi n and their anions determined to examine the nature of bonding and their relative stabilities.
使用CCSD(T)/aug-cc-pVTZ-DK//MP2/6-31G(2df,p)、G4//MP2/6-31G(2df,p)以及B3LYP/6-311+G*基组,系统研究了铜掺杂小硅团簇CuSiₙ(n = 4 - 10)及其阴离子的结构和能量。评估了用于预测能量和热力学性质的方法的性能。通过比较实验数据[Xu等人(2012年),《化学物理杂志》136:104308]和理论计算结果,得出CCSD(T)结果非常准确且表现最佳的结论;其与实验数据的平均绝对偏差为0.043电子伏特。实验结果与CCSD(T)计算结果在垂直脱附能(VDE)方面的出色吻合表明,本文给出的CuSiₙ⁻(n = 4 - 10)的基态结构是可靠的。对于CuSi₁₀,基于CCSD(T)计算结果和之前CuSi₁₀⁻的光电子能谱(Xu等人,同前引文),将实验绝热电子亲和能(AEA)指定为2.90±0.08电子伏特、VDE指定为3.90±0.08电子伏特比分别指定为3.46±0.08电子伏特和3.62±0.08电子伏特更为合理。除CuSi₇外,CuSiₙ(n = 4 - 10)的AEA与实验数据高度吻合,表明本文报道的CuSiₙ(n = 4 - 6、8 - 10)的基态结构是可靠的。有人认为CuSi₁₀是最小的内包式基态结构。然而,给CuSi₁₀添加一个额外电子会使Cu原子从中心位置移出,形成CuSi₁₀⁻的外包式基态结构。通过确定Cu从CuSiₙ及其阴离子的电荷转移和解离能,来研究键合性质及其相对稳定性。