量子电子学报2025，Vol.42Issue(3)：304-312,9.DOI:10.3969/j.issn.1007-5461.2025.03.002
外电场下5-溴-2-氟硝基苯分子的解离及激发特性
Dissociation and excitation properties of 5-bromo-2-fluoronitrobenzene molecule under external electric field
摘要
Abstract
The effects of external electric field(0-0.040 arb.units)on the structure parameter,natural bond orbital charge distribution,electric dipole moment,energy gap and potential energy curve of 5-bromo-2-fluoronitrobenzene(5Br2FNB)molecule were investigated by using DFT/B3LYP/6-311+G(d,p)method in this work.The excitation energy and hole-electron of the molecule under different external electric fields were also studied by TD-DFT/B3LYP/6-311+G(d,p)method.The results show that,with the increase of external electric field intensity,the bond length of C(5)-Br(10)and the electronegativity of Br(10)atom increases,and the HOMO and LUMO energy,energy gap,excitation energy and potential barrier all show an overall decreasing trend,indicating that the stability of the molecule decreases gradually.All the analyses indicate that C(5)-Br(10)bond dissociation has occurred when the external electric field intensity exceeds 0.030 arb.units.According to the hole-electron analysis,it is shown that when the external electric field intensity range is 0-0.010 arb.units,the S0→S1 excitation of the molecule is local excitation,and when the external electric field intensity range is 0.020-0.030 arb.units,S0→S1 is charge transfer excitation.However,when the external electric field is 0.040 arb.units,S0→S1 transforms again into local excitation,which means that the charges of molecule begin to redistribute after the C(5)-Br(10)bond breakage,further confirming that the C(5)-Br(10)bond begins to dissociate when the external electric field intensity reaches 0.030 arb.units.This study has important reference value for deeper understanding of the dissociation mechanism of 5Br2FNB molecule under external electric fields.关键词
光谱学/5-溴-2-氟硝基苯/密度泛函理论/外电场/解离/空穴-电子分析Key words
spectroscopy/5-bromo-2-fluoronitrobenzene/density functional theory/external electric field/dissociation/hole-electron analysis分类
物理学引用本文复制引用
张敏,秦晨..外电场下5-溴-2-氟硝基苯分子的解离及激发特性[J].量子电子学报,2025,42(3):304-312,9.基金项目
新疆维吾尔自治区自然科学基金(2022D01A222),国家自然科学基金(12364035) （2022D01A222）
