三氯化硼离子C^(2)A″_(2)态光电子谱的理论研究  

Theoretical study on photoelectron spectrum of BCl_(3)^(+) cation in C^(2)A″_(2) state

作　　者：宁小寒 于同坡 陈燕[2] 单宝坤 周晓国 刘世林 NING Xiaohan;YU Tongpo;CHEN Yan;SHAN Baokun;ZHOU Xiaoguo;LIU Shilin(Hefei National Laboratory for Physical Sciences at Microscale,Department of Chemical Physics,University of Science and Technology of China,Hefei 230026,China;National Institute of Metrology,Beijing 100013,China)

机构地区：[1]中国科学技术大学,合肥微尺度物质科学国家研究中心,化学物理系,安徽合肥230026 [2]中国计量科学研究院,北京100013

出　　处：《量子电子学报》2021年第5期691-698,共8页Chinese Journal of Quantum Electronics

基　　金：国家重点研发计划,2016YFF0200502;国家自然科学基金,21873089,22073088。

摘　　要：应用密度泛函理论对BCl_(3)^(+)离子C^(2)A″_(2)态的电子能谱进行了深入研究。在aug-cc-pvtz基组下,分别使用PBE0、ωB97XD、M06-2X三种泛函优化了中性BCl_(3)分子、BCl_(3)^(+)离子基态X_(2)A′_(2)以及C^(2)A″_(2)态的分子结构,并计算了相应振动频率和电离过程BCl_(3)(X^(1)A_(1))→BCl_(3)^(+)(C^(2)A″_(2))跃迁的Franck-Condon因子,从而得到了该跃迁对应的拟合电子能谱。通过与已有的高分辨实验电子能谱对比,实现了BCl_(3)^(+)离子C^(2)A″_(2)态实验光谱的高精度光谱拟合,进而对实验振动序列做了清晰可靠的归属,得到BCl+3离子C^(2)A″_(2)态的绝热电离能AIE、垂直电离能VIE分别为(14.298±0.028)eV、(14.405±0.028)eV,从而修正了已报道电离能的错误数据。Density functional theory has been applied to in-depth study on photoelectron spectrum of BCl_(3)^(+)cation in the C^(2)A″_(2)state.With the aug-cc-pvtz basis set,the geometries of neutral BCl_(3),BCl_(3)^(+)cation in ground state,X^(2)A′2,and an electronically excited state,C^(2)A″_(2),are optimized using three theory levels of PBE0,ωB97XD and M06-2X.Then the corresponding vibrational frequencies and the Franck-Condon factors of the BCl_(3)(X1A1)→BCl_(3)^(+)(C^(2)A″_(2))transition are calculated,and the photoelectron spectrum is simulated.By comparing with the high-resolution photoelectron spectrum obtained previously in experiment,the photoelectron spectrum of the C^(2)A″_(2)band is successfully simulated,then reliable assignments for the observed vibrational progression are obtained.Based on these vibrational assignments,the adiabatic ionization energy(AIE)and vertical ionization energy(VIE)for BCl_(3)^(+)cation in the C^(2)A″_(2)state have been determined directly as AIE(C^(2)A″_(2))=(14.298±0.028)eV and VIE(C^(2)A″_(2))=(14.405±0.028)eV,respectively,and their wrong values reported in previous experiments have been corrected.

关 键 词：光谱学 电离能 密度泛函理论 光电离 电子激发态 

分 类 号：O644.1[理学—物理化学]