计算物理 ›› 2003, Vol. 20 ›› Issue (1): 88-90.

• 论文 • 上一篇    下一篇

氘代甲烷几何构型及物性的量子化学研究

陆春海1, 陈文凯2, 廖俊生1, 王怀胜1, 汪小琳1, 孙颖1   

  1. 1. 中国工程物理研究院, 四川 绵阳 621900;
    2. 福州大学化学系, 福建 福州 360002
  • 收稿日期:2001-03-07 修回日期:2001-09-24 出版日期:2003-01-25 发布日期:2003-01-25
  • 作者简介:陆春海(1968-),男,浙江杭州,高级工程师,硕士生,主要从事原子光谱和计算量化研究.
  • 基金资助:
    中国工程物理研究院科学基金资助项目(20000557)

Geometric Configuration and Properties of Methane Series

LU Chun-hai1, CHEN Wen-kai2, LIAO Jun-sheng1, WANG Huai-sheng1, WANG Xiao-iin1, SUN Yin1   

  1. 1. China Academy of Engineering Physics, Mianyang 621900, China;
    2. Department of Chemistry, Fuzhou University, Fuzhou 360002, China
  • Received:2001-03-07 Revised:2001-09-24 Online:2003-01-25 Published:2003-01-25

摘要: 用HF/6-31G**、密度泛函方法B3LYP/31G**、二级微扰MP2/6-31G**、四级微扰MP4/6-31G**方法对甲烷和氘代甲烷进行几何构型全优化,并将优化的结果与实验值进行比较.用上述4种方法对甲烷和氘代甲烷分子进行分子的振动基频计算.密度泛函、二级微扰、四级微扰优于HF/6-31G**,尤其是密度泛函、四级微扰方法.密度泛函方法所用的机时远小于微扰方法.不同方法计算所得的氘代甲烷振动频率值与实验值的最大误差为10.4%,最小误差为2.0%.

关键词: 甲烷, 氘, 从头算, DFT方法, 振动基频

Abstract: Ab initio restricted Hatree-Fock(RHF) calculations, Moller-Plesset correction calculations of the correlation energy, and the density functional theoretical calculations using B3' exchange and Lee-Yang-Parr's correlation functional(B3LYP) with 6-31G** basic set are compared by optimizing the equilibrium structure of CD4 and CH4 and studying their fundamental vibration frequencies. The results are better than HF's, which are obtained by MP2, DFT, MP4 methods. But MP4 method needs too much CPU time. B3LYP is the best choice. The range of relative errors is from 2.0% to 10.4% between the calculated fundamental vibration frequencies and the observed ones.

Key words: methane, deuterium, ab initio, DFT method, fundamentai vibration freguency

中图分类号: