大学物理 ›› 2020, Vol. 39 ›› Issue (11): 44-48.doi: 10.16854 /j.cnki.1000-0712.190417

• 物理实验 • 上一篇    下一篇

外电场下四氯甲烷光谱特性和解离特性研究

袁园,唐延林,袁荔,施斌   

  1. 贵州大学物理学院,贵州贵阳550025
  • 收稿日期:2019-09-16 修回日期:2020-03-03 出版日期:2020-11-10 发布日期:2020-11-17
  • 通讯作者: 唐延林,E-mail: tylgzu@ 163.com
  • 作者简介:袁园( 1983—) ,男,汉族,湖北黄冈人,贵州大学物理学院2017 级硕士,主要从事分子光谱和电磁场方面的计算研究工作.
  • 基金资助:
    国家自然科学基金( 11164004) ; 贵州省光子科学与技术创新人才团队项目( 20154017) 资助

Spectral and separation characteristics of tetrachloromethane under external electric field

YUAN Yuan,TANG Yan-lin,YUAN Li,SHI Bin   

  1. School of Physics,Guizhou University,Guiyang,Guizhou 550025,China
  • Received:2019-09-16 Revised:2020-03-03 Online:2020-11-10 Published:2020-11-17

摘要: 采用B3LYP /6-311G( d,p) 方法和基组优化四氯甲烷分子,研究四氯甲烷在外加电场下的总能量、第一电离能、电子亲和势、电负性、红外光谱、拉曼光谱及解离势能面等,并讨论外电场对该分子的影响. 结果表明: 无电场时采用B3LYP /6-311g( d,p) 基组优化效果与实验测量结果相吻合; 总能量、第一电离能、电子亲和势的绝对值与电场的方向无关,总能量和第一电离能随着电场强度的增强而减小,电子亲和势随着电场强度的增强而增加,电负性随正向电场的增强而减小,随负向电场的增强而先增加后减小; 红外吸收强度随电场的增强先迅速减小后增大,红外最强吸收峰、拉曼峰随正向电场呈现红移,红外最强吸收峰随负向电场呈现蓝移; 随外电场增大,C1-Cl5 键势阱值逐渐降低、能垒逐渐减小,键束缚能力逐渐减弱,当外电场增加到-0.0015 a.u.时,C1-Cl5 键能垒消失,分子发生解离.本研究对四氯甲烷及类似有毒有机污染物的降解提供新思路.

关键词: 外电场, 氯甲烷, 负性, 光谱特性, 解离

Abstract: Under applied electric field,the total energy,first ionization energy,electron affinity,electronegativity,

infrared spectroscopy,Raman spectroscopy and dissociation potential energy surface of tetrachloromethane are

studied by using B3LYP /6-311G( d,p) method and group optimization method. The effects of external electric field

on the molecular are discussed. The results show that the optimization effect of B3LYP /6-311G( d,p) base set without

electric field is consistent with the experimental results; the absolute values of total energy,first ionization

energy and electron affinity are independent of the direction of electric field,and the total energy and first ionization

energy decrease with the increase of electric field intensity,while the electron affinity increases with the increase of

electric field intensity. The electronegativity decreases with the increase of the positive electric field,and increases

first and then decreases with the increase of the negative electric field; the infrared absorption intensity decreases rapidly

at first and then increases with the increase of the electric field; the infrared strongest absorption peaks and Raman

peaks show a red shift with the positive electric field,and the infrared strongest absorption peaks show a blue

shift with the negative electric field. With the increase of external electric field,C1-Cl5 bond potential well value decreases

gradually,energy barrier decreases gradually,bond binding ability decreases gradually. When the external electric

field increases to -0.0015 a.u.,the C1-Cl5 bond barrier disappears and the molecule dissociates. External electric

field provides a new idea for the degradation of toxic organic pollutant tetrachloromethane and similar toxic substances.

Key words: external electric field, tetrachloromethane, electronegativity, spectral properties, dissociation