Spectrum and Dissociation Characteristics of Methyl Bromide in External Electric Field

doi:10.19596/j.cnki.1001-246x.7736

Abstract

Abstract: B3LYP/6-311++g(d,p) method is adopted to optimize ground state structure of CH₃Br molecule. Bond length, energy gap and dissociation potential energy surface of CH₃Br molecule in external electric field (0-0.05 a.u.) are studied. It shows that direction and magnitude of applied electric field is of great significance to molecular structure and potential energy surface. With negative electric field (C-Br bond direction) increases from 0 to 0.05 a.u., bond length of C-Br bond decreases first and then increases. Bond length of C-H bond increases gradually. Molecular energy gap E_G decreases gradually. Vibrational frequency of C-Br bond increases while IR vibration frequency decreases. It is found that potential energy of methyl bromide molecule decreases and dissociation barrier decreases, which indicating that CH₃Br molecule is easy to be excited and dissociated in external electric field.

Key words: external electric field, dissociation, DFT, methyl bromide

CLC Number:

O604

WANG Xiaoqing, LIU Yuzhu, YIN Wenyi, LI Jinhua. Spectrum and Dissociation Characteristics of Methyl Bromide in External Electric Field[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2018, 35(5): 619-625.

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