13.9-15.1eV光子能量范围二氟二氯甲烷的阈值光电子能谱研究  

Threshold Photoelectron Spectrum of CF_(2)Cl_(2) in Photon Energy Range of 13.9‒15.1 eV

作　　者：单宝坤 杨新浪 于同坡 陈燕 张宁 周晓国[1] 刘世林[1] Baokun Shan;Xinlang Yang;Tongpo Yu;Yan Chen;Ning Zhang;Xiaoguo Zhou;Shilin Liu(Department of Chemical Physics,University of Science and Technology of China,Hefei 230026,China;Department of Physics,Hefei University of Technology,Hefei 230009,China;National Synchrotron Radiation Laboratory,University of Science and Technology of China,Hefei 230029,China)

机构地区：[1]中国科学技术大学化学物理系,合肥230026 [2]合肥工业大学物理系,合肥230009 [3]中国科学技术大学国家同步辐射实验室,合肥230029

出　　处：《Chinese Journal of Chemical Physics》2024年第2期303-312,I0103,共11页化学物理学报（英文）

基　　金：This work was financially sup-ported by the National Natural Science Foundation of China(No.22073088 and No.22027801)。

摘　　要：本文利用阈值光电子-光离子符合测量与密度泛函理论计算重新研究了二氟二氯甲烷的阈值光电子谱.在13.9-15.1eV能量范围,可以清晰地观察到D^(2)B_(2)态的一系列振动峰.在M06-2X/aug-cc-pVTZ计算水平上对二氟二氯甲烷中性分子基态及D^(2)B_(2)离子激发态进行了构型优化和振动频率分析,获得了与实验光谱一致的弗兰克-康登拟合光谱。得到了D^(2)B_(2)离子态精确的绝热电离能(14.125±0.005eV)和垂直电离能(14.355±0.005eV),v1^(+)和v3^(+)模式的振动频率(1178cm^(-1)和361 cm^(-1)),以及v3^(+)模对应的非谐性参数(3.42 cm^(-1)).Threshold photoelectron spectroscopy of dichlorodifluoromethane(CF_(2)Cl_(2))has been re-investigated using a combination of photoelectron-photoion coincidence measurement and density functional theory calculations.For the D^(2)B_(2) band of threshold photoionization spectra in the energy range of 13.9‒15.1 eV,a series vibrational peaks were clearly observed.Using the optimized geometries and vibrational frequencies of the CF_(2)Cl_(2) neutral and its cations in the D2B2 ionic state at the M06-2X/aug-cc-pVTZ level of theory,Franck-Condon factor simulations were carried out,and showed perfect agreement with the experimental spectra.Accordingly,the satisfactory vibrational assignments for the D^(2)B_(2) band were achieved,and the adiabatic and vertical ionization energies to the D^(2)B_(2) ionic state were determined as 14.125±0.005 eV and 14.355±0.005 eV,respectively.Moreover,vibrational frequencies of theν1^(+)andν3^(+)modes were 1178 cm^(−1) and 361 cm^(−1),respectively,as well as the anharmonic parameter for theν3^(+)mode of 3.42 cm^(−1).

关 键 词：二氟二氯甲烷 光电子谱 振动光谱 光电离 符合测量 

分 类 号：O657.63[理学—分析化学] O644[理学—化学]