摘要
基于密度泛函B3LYP/6-311+G(2df)理论,本文对BnCmNl(n+m+l≤3)团簇进行结构优化和简谐振动频率计算.结果表明,硼碳氮双体团簇BnCmNl(n+m+l=2)的基态分别为B2(3∑g),BC(4∑-),BN(3∑),C2(1∑g),CN(2∑),N2(1∑g),其键能遵循顺序:N-N>C-N>C-C>B-N>C-B>B-B;三体团簇BnCmNl(n+m+l=3)的基态中,B2C(C2v,1A1)、C2B(Cs,2A′)、N2B(C2v,2A1)采取环状结构,而BCN(C∞v,1∑)、B2N(D∞h,2∑u)、C2N(D∞h,2∏g)、CN2(D∞h,3∑g)则采取直线结构.分析表明相对强键和芳香环的形成是主导硼碳氮三体团簇同分异构体稳定性的决定因素.在相同的理论水平上,所有基态都给出预测的红外频率和相应的振动强度.
Based on the density functional theory, geometry optimizations and harmonic-vibrational frequency computations have been performed for clusters BnCmNl(n+m+l≤3) in this article. Optimized results indicate:the ground states of dimer BnCmNl(n + m + l =2) clusters are B2(^3∑g),BC(^4∑-),BN(^3∑),C2(^1∑g),CN(^2∑),N2(^1∑g), respectively, and they follow a bond energy order of N - N〉C- N〉C- C〉B- N〉C-B〉B-B. Among the ground states of BnCmNl(n + m + l =3) trimer clusters,B2C(C2υ,^1A1)、C2B(Cs,^2A′)and N2B(C2υ,^2A1) adopt cyclic structures, while BCN(C∞υ,^1∑)、B2N(D∞h,^2∑u)、C2N(D∞h,^2Ⅱg)and CN2(D∞h,^3∑g)adopt linear ones. Results also show that the formation of the relative strong bond (s) or aromatic ring-like structure predominate (s) the stabilities of their isomers of B-C-N trimer cluster systems. At the same theory level, predicted vibrational frequencies and corresponding intensities for all the ground states are also presented in detail.
出处
《原子与分子物理学报》
CAS
CSCD
北大核心
2007年第5期1028-1034,共7页
Journal of Atomic and Molecular Physics
基金
韩山师范学院青年科研基金
关键词
碳氮硼团簇
密度泛涵理论
芳香性
红外光谱
Bn Cm Nl cluster, density functional theory, aromaticity, infrared spectrum