Bonding properties and isomeric conversion pathways from exohedral to endohedral BeGe8 clusters

作者：Hung Yu Ming^*; Ho Gong Ming; Zhang Zhen Feng

来源：Computational and Theoretical Chemistry, 2012, 999: 154-161.

DOI：10.1016/j.comptc.2012.08.029

• Be@Ge-8 cluster
• Endohedral clusters
• Hirshfeld charges
• Mayer total valences
• Wade-Mingos rules
• Isomeric conversion pathways

The B3LYP/6-31G* method was employed to optimize the BeGe8 isomeric structures. Some adsorptive precursors can be formed without experiencing activation energy. Hirshfeld charges and Mayer total valences analysis show that a larger extent of back-donation leading to a higher Be negativity and hypervalency. All Be-Ge bonds are covalent, not ionic, according to charge partitions and M.O. analysis. Cluster energies obtained by the 6-31G* and 6-311++G(3df) basis sets show significant difference and the 6-311++G(3df) energies correlate better with bonding properties. The 6-31G* ground state is a cubic Be@Ge-8 that agrees with the literature. However, the 6-311++G(3df) ground state is a cube-distorted C-2v Be@Ge-8 with less cage strain. The Wade Mingos rule was added to explain this change. Conversion pathways from the lowest-energetic adsorptive exohedrons to the lowest-energetic endohedrons have been explored and the Mayer bond orders assisted to describe part of the conversion progress.

• 出版日期2012-11-1