物理化学学报 >> 1987, Vol. 3 >> Issue (04): 418-424.doi: 10.3866/PKU.WHXB19870416

研究论文 上一篇    下一篇

环脲硝胺化合物的性能和电子结构之间的关系
I. 羰基伸缩频率和键级、双原子作用能的近似线性相关

肖鹤鸣; 邓娅; 陈里   

  1. 华东工学院, 南京
  • 收稿日期:1986-03-17 修回日期:1987-01-06 发布日期:1987-08-15

A RELATIONSHIPS BETWEEN PROPERTIES AND ELECTRONIC STRUCTURE OF CYCLOUREA NITRO-AMINE COMPOUNDS
I. Approximate linear relations of vco and Mco, Eco and Ecor

Xiao Heming; Deng Ya; Chen Li   

  1. East China Institute of Technology; Nanjing
  • Received:1986-03-17 Revised:1987-01-06 Published:1987-08-15

摘要: 本文通过CNDO/2计算研究环脲硝胺同系化合C=O基伸缩频率与所得计算参量的关系。获得的结果是: 羰基伸缩频率实验值与C=O的Mulliken键级、双原子作用能等计算值之间, 存在近似的线性关系, 对现有的9个文献化合物和新合成的2,4,6,8-四硝基半甘脲的~γCO和计算参量作了线性回归处理, 相关系数为0.95。讨论了一些理论有机的传统观点与本文结果的关系。

Abstract: This paper is the first one about research of the relations between properties and electronic structure for cyclourea nitro-amine compounds by CNDO/2 method, It is found that the stretch vibration frequency (v_(CO)) of carbonyl in their molecules are linearly related with the Mulliken bond order (M_(CO)) of bond C=O and the two-atom energy (E_(CO)) between the C and O atoms, i.e., there are following linear relations:
v_(CO)=-5208+7394M_(CO) r=0.95 (1)
v_(CO)=-6057-4842E_(CO) r=-0.95 (2)
where r is correlation coefficient. Therefore, the position of the characteristic absorptive peak of the carbonyl of the some compounds in this series can be predicted by theoritical calculations and using equation (1) or (2). For example, for 2,4,6,8-tetranitro-semiglycoluril, the predicted ν_(co) values (1813 and 1826 cm~(-1)) are in good agreement with the experimental value (1825 cm~(-1)). According to theoretical analysis and based on results of CNDO/2 computations, it is shown that there exist the approximate linear relationship between the Mulliken bond order (M_(AB)) (from “population analysis”) and the two-atom energy (E_(AB)) (from “energy seperation”) for same type of bond (A—B) in cycloureide nitramine compounds, and it is also shown that M_(AB) is rigorously directly proportional to the resonace integral energy (E~r_(AB)), which is a term included in E_(AB). These indexes obtained by CNDO/2 calculations agree with each other for the measure of the bond strength and the stretch vibration frequency of the carbonyl. Else, the relation between the previous results and the classical review point of the theoritical organic chemistry are also discussed in this paper.