外电场下二溴一氯甲烷分子的光谱特征和解离特性

Dissociation properties and spectra of dibromochloromethane under external electric field

在Semi-empirical方法AM1基组下研究了外电场(0~0.040 arb.units)作用下二溴一氯甲烷分子的光谱特征和解离特性:外电场对分子键长、偶极矩、总能量、能级分布规律、红外光谱等的影响;通过计算得到解离势能曲线。结果表明,沿着y轴方向加外电场,强度从0 arb.units增加到0.040 arb.units时:二溴一氯甲烷分子键长明显拉长,分子偶极矩增大;总能量先增大后减小;能隙随着电场的增大而减小;红外光谱随外电场的增强出现红移或蓝移现象。此外,随着外加电场的增强,势垒降低,解离需要的能量逐渐减小,当外电场达到0.040 arb.units时,分子发生解离。计算结果说明分子1C-3Cl键在外电场下容易断裂,这为二溴一氯甲烷的降解提供了理论依据。

The Semi-empirical method was used to study the spectral and dissociation characteristics of dibromochloromethane molecules under the action of external electric field(0-0.040 arb.units)on the AM1 basis set,the influences of external electric field on bond length,dipole moment,total energy,energy level distribution and infrared spectrum were calculated,and the dissociation potential energy curve was obtained.The results show that,when the external electric field increases from 0 arb.units to 0.040 arb.units along the y-axis direction,the bond length of dibromochloromethane molecule is obviously elongated,the molecular dipole moment increases,and the total energy first increases and then decreases.At the same time,with the increase of external electric field,the energy gap decreases,and the infrared spectrum appears red shift or blue shift.In addition,with the increase of applied electric field,the potential barrier decreases and the energy required for dissociation gradually decreases.When the external electric field reaches 0.040 arb.units,the molecule will dissociate.It is shown in this work that the 1C-3Cl bond of is dibromochloromethane molecule is easily broken under the external electric field,which provides a theoretical basis for the degradation of dibromochloromethane.