大气与环境光学学报 ›› 2017, Vol. 12 ›› Issue (3): 195-201.

• 环境光学监测 • 上一篇    下一篇

外电场下氯甲烷的光谱和解离特性

王啸卿1,3, 刘玉柱1,3†, 李相鸿2, 王俊锋1,3, 林华1,3, 秦朝朝4   

  1. (1南京信息工程大学物理与光电工程学院, 江苏 南京 210044; 
    2皖南医学院弋矶山医院临床药学部, 安徽 芜湖 241001; 
    3江苏省大气环境与装备技术协同创新中心, 江苏 南京 210044; 
    4河南师范大学物理系, 河南 新乡 453007 )
  • 收稿日期:2016-07-08 修回日期:2016-08-29 出版日期:2017-05-28 发布日期:2017-05-18
  • 通讯作者: 刘玉柱(1984-),男,汉族,安徽六安人,教授,博士,从事大气环境光学与大气光化学方面的研究。 E-mail:yuzhu.liu@gmail.com
  • 作者简介:王啸卿(1994-),男,汉族,江苏扬州人,从事分子激光光谱方面的研究。
  • 基金资助:

    Supported by National Natural Science Foundation of China (国家自然科学基金, 11304157, U1404112, 11504175), Six Talent Peaks Project in Jiangsu Province (江苏省六大人才高峰高层次人才项目, 2015-JNHB-011), College Students Practice Innovative Training Program of NUIST (南京信息工程大学大学生实践创新训练计划项目, 201610300042).

Spectra and Dissociation Characteristics of Methyl Chloride Under External Electric Field

  1. (1 School of Physics and Opto-Electronics Engineering, Nanjing University of Information Science & Technology, Nanjing 210044, China; 2 Institute of Clinical Pharmacology, Yijishan Hospital of Wannan Medical College, Wuhu 241001, China; 
    3 Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology, Nanjing 210044, China; 
    4 Department of Physics, Henan Normal University, Xinxiang 453007, China)
  • Received:2016-07-08 Revised:2016-08-29 Published:2017-05-28 Online:2017-05-18

摘要:

为了研究外电场对氯甲烷分子光谱和解离特性的影响,采用密度泛函理论(density functional theory,DFT)B3LYP方法在6-311++G(d,p)基组水平上研究了不同外电场(-0.03 a.u.~0.03 a.u.)对氯甲烷分子结构以及解离特性的影响,包括键长、分子能隙、红外光谱以及解离势能面等. 计算结果表明,随着Z方向(C-Cl连线方向)外电场从-0.03 a.u.逐渐增加到0.03 a.u., C-Cl键的键长逐渐增大而C-H键的键长几乎不变, 分子能隙EG先增大后减小,当外加电场等于0.01 a.u.时达到峰值. C-Cl 伸缩(stretching, STR) 振动的频率是逐渐减小的, 而红外光谱(infrared,IR)振动强度是逐渐增加的. 通过进一步计算研究发现, 随着外电场(0~0.03 a.u.)继续增强, CH3Cl分子的势能曲线逐渐降低, 解离能逐渐减小. 当外电场大约是0.04 a.u.时解离能最小,发生解离. 因此,可以通过改变外电场来控制CH3Cl分子的降解.

关键词: 氯甲烷, 外电场, 解离, 红外光谱, 分子能隙

Abstract:

In order to analyze the influence of external electric field on the molecular spectra and dissociation of methyl chloride, density functional (DFT) theory at B3LYP/6-311G++(d,p) level is used to investigate the influence on the molecular structure of the chloromethane molecule and dissociation properties under different external electric field (-0.03~0.03 a.u.), including molecular bond length, energy gap, IR spectra, dissociation curve and so on. The calculation results show that with external electric field increase from -0.03 a.u to 0.03 a.u step by step, on the Z direction(C-Cl line), C-Cl bond length increases and C-H bond length is almost the same. When the external electric field is equal to 0.01 a.u, the peak value is reached. The molecular energy gap increases and then decreases. The C-Cl stretching (STR) vibration frequency is gradually decreases, while infrared (IR) vibration intensity gradually increases. Further research and analysis indicate that with the continuous increase of the external electric field (0~0.03 a.u), the energy curve of CH3Cl molecule decreases gradually and the dissociation decreases too. When the external electric field is about 0.04 a.u, the dissociation energy is at the minimum, and the dissociation occurs. Therefore, it can control the degradation of the CH3Cl molecule by changing the external electric field.

Key words: chloromethane, external electronic field, degradation; spectra, molecular energy gap

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