物理化学学报 >> 2005, Vol. 21 >> Issue (05): 479-484.doi: 10.3866/PKU.WHXB20050504

研究论文 上一篇    下一篇

内含式化合物X@B12P12的结构与稳定性研究

武海顺; 张竹霞   

  1. 山西师范大学材料化学研究所, 临汾   041004
  • 收稿日期:2004-09-03 修回日期:2004-12-02 发布日期:2005-05-15
  • 通讯作者: 武海顺 E-mail:wuhs@dns.sxtu.edu.cn

Structure and Stability of Endohedral Complexes X@B12P12

WU Hai-Shun; ZHANG Zhu-Xia   

  1. Institute of Chemistry and Materials Science,Shanxi Normal University,Linfen   041004
  • Received:2004-09-03 Revised:2004-12-02 Published:2005-05-15
  • Contact: WU Hai-Shun E-mail:wuhs@dns.sxtu.edu.cn

摘要: 采用B3LYP/6-31G*方法,对内含式化合物X@B12P12(X=Li0/+、Na0/+、K0/+、Be0/2+、Mg0/2+、Ca0/2+、H和He)的不同对称性构型进行了计算,讨论其最稳定构型的几何参数、布居分析、偶极矩、电离势、包含能、振动频率、能隙和自旋密度. 发现在X@B12P12化合物中,客体X=Li、Na0/+、K0/+、Mg0/2+、Ca0/2+和He处在偏离笼的中心0.006 nm的半径内. Be2+沿着C3轴偏离中心点0.279 nm. 在Be@B12P12和H@B12P12的基态结构中,Be和H与笼上的B原子成键. 除Li@B12P12、 Be2+@B12P12和He@ B12P12外, 其余结构为Cs对称稳定构型.

关键词: 内含式化合物, 偶极矩, 包含能, 能隙, 自旋密度

Abstract: All structures of X@B12P12 (X=Li0/+, Na0/+, K0/+, Be0/2+, Mg0/2+, Ca0/2+, H and He) are optimized at the B3LYP/6-31G-density functional level of theory, and the corresponding frequency calculations at the same level are used to characterize the optimized structures with energy minima without imaginary frequencies. The geometries,natural bond orbitals (NBO). dipole moments, adiabatic ionization potentials, inclusion energies, vibrational frequencies, energy gaps and spin densities are also discussed. The calculations predict that X= Li, Na0/+, K0/+, Mg0/2+, Ca0/2+ and He are in the vicinity of 0.006 nm of the cage center, and Be2+ is displaced by 0.279 nm from the cage center along the threefold axis of B12P12. Be@B12P12 and H@B12P12 have endohedral Be-B and H-B bonds respectively. Except for Li@B12P12, Be2+@B12P12, and He@B12P12, all conformations favor Cs symmetry.

Key words: Endohedral complexes, Dipole moment, Inclusion energies, Energy gap, Spin density