Theoretical observation of hexaatomic molecules containing pentacoordinate planar carbon

• 来源期刊: 中国科学B辑(英文版)
• 年，卷（期）: 2008,（11）
• 页码范围: 1030-1035
• 页数: 6页
• 语种: 英文
• DOI: 10.1007/s11426-008-0121-5

摘要

The smallest molecules up to date containing a D5h pentacoordinate planar carbon (PPC) atom, CBe5 and CBe54-, are presented by means of ab initio calculations. To gain a better understanding about which electronic factors contribute to their stabilization, natural bond orbital (NBO) analysis and the nucleus independent chemical shifts (NlCS) were calculated. The data reported here suggest that D5h CBe5 is a aromaticity in nature, while in D5h CBe54- Tr aromaticity is dominating. The classical octet rule is well satisfied in both molecules, and is one of the fundamental reasons to understand the stability of the pentagon structures. The Be5 ring serves as σ donor in D5h CBe5, and Tr-acceptor in D5h CBe54-. The D5h CBe54- possessing 18 valence electrons with a closed-shell electron configuration is the most plau-sible candidate for experimental detection.