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采用键表酉群方法对Ｃ６Ｈ５Ｆ、Ｃ６Ｈ５ＯＨ和Ｃ６Ｈ５ＮＨ２中的电子离域现象进行了计算和分析，讨论了取代苯的价键描述特性，并计算了取代基的π电子离域能．结果表明离子结构成分与离域能有直接关系，即离子成分越多，电子离域能越大．／６－３１Ｇ基组及“分子中的原子”方法将电荷密度分区积分得到各原子上的电荷集居数，并将此结果与取代苯的反应性能进行了比较。为在价键意义上分析和理解取代基对苯环电子结构及其反应性能的影响，本文对３个典型的取代苯Ｐｈ－Ｘ（Ｘ＝Ｆ，ＯＨ，ＮＨ２）进行了初步的价键计算和讨论．１计算方法及构型在键表酉群方法中［５］，体系的一个共振结构可用一个价键结构函数即键表ψ（ｋ）来描述，相应的体系总波函数Ψ可表示为Ｍ个正则键表的线性组合：式（１）便构成了键表相互作用（ＢＴＩ）计算方法［６］的基础．键表对体系的结构贡献定义为：原子轨道ｑ上的电荷集居数定义为：式中ｍｑ（ｋ）可取０、１或２，分别对应于键表ψ（ｋ）中原子轨道ｑ出现０、１或２次．为简比计算，我们将取代苯的σ骨架用ＨＦ分子轨道固定［７］，这样仅需考虑π电子及轨道．原子轨道积分及ＨＦ－ＳＣＦ计算采用Ｇａｕｓｓｉａｎ８０程序．联系人及第一作者：莫亦荣，男，２９?
The electron delocalization in C6H5F, C6H5OH and C6H5NH2 was calculated and analyzed by using the key-table unitary group method. The valence bond description of the substituted benzene was discussed and the π-electron delocalization energy of the substituent was calculated. The results show that ionic structure and delocalization have a direct relationship, that is, the more ion components, the greater the delocalization energy. / 6-31G basis set and the “atom in the molecule” method, the charge density partition is integrated to obtain the number of charge clusters on each atom, and the result is compared with that of the substituted benzene. In order to analyze and understand the effect of substituents on the electronic structure of benzene ring and its reaction performance in the sense of valence bond, the initial valence bond calculations of three typical substituted benzene Ph-X (X = F, OH, NH2) And discussion. 1 Calculation method and configuration In the key table unitary group method [5], a resonance structure of the system can be described by a valence bond structure function, namely the key table ψ (k). The total system wave function Ψ can be expressed as M Linear Combination of Regular Key Tables: Equation (1) forms the basis of the Key Table Interaction (BTI) calculation [6]. The contribution of the key table to the system is defined as: The number of charge sets on the orbital q is defined as: where mq (k) is 0, 1 or 2, corresponding to q in the orbit q of the key table ψ (k) , 1 or 2 times. For the simple ratio calculation, we replace the σ skeleton of benzene with HF molecular orbitals [7], so we only need to consider π electron and orbit. Atomic Orbit Integration and HF-SCF calculations using Gaussian80 program. Contacts and first author: Mo Rong also, male, 29?