PbBr分子光谱性质的理论研究  

Theoretical study of spectroscopic properties of PbBr molecule

作　　者：蔡雨桐 李瑞[2] 桑纪群 刘晓军[1] 任晓辉[1] CAI Yutong;LI Rui;SANG Jiqun;LIU Xiaojun;REN Xiaohui(School of Science,Qiqihar University,Qiqihar 161006,China;School of Teacher Education,Qiqihar University,Qiqihar 161006,China)

机构地区：[1]齐齐哈尔大学理学院,黑龙江齐齐哈尔161006 [2]齐齐哈尔大学教师教育学院,黑龙江齐齐哈尔161006

出　　处：《高师理科学刊》2024年第4期54-59,共6页Journal of Science of Teachers＇College and University

基　　金：黑龙江省平台开放课题(DWCGQKF202104);黑龙江省省属高等学校基本科研业务费青年创新人才项目(135509217);齐齐哈尔大学学位与研究生教育教学改革研究项目(JGXM_QUG_2022015)。

摘　　要：采用高精度多参考组态相互作用(MRCI)方法计算了PbBr分子的电子结构.为了保证计算精度,在计算过程中考虑了戴维森修正(+Q)、芯壳层-价壳层(CV)电子相关效应.基于计算获得的能量,绘制了PbBr分子能量最低的三条解离极限对应的23个Λ-S态的势能曲线(PECs).根据计算得到的势能曲线,计算了束缚态的光谱常数,计算结果与之前研究结果吻合较好.应用组态相互作用方法计算了Λ-S态的电偶极矩,在避免交叉点,Λ-S态的偶极矩(DMs)表现出突变,这是由于这些态的主要电子组态成分发生变化.绘制了2^(2)Σ^(+),3^(2)Σ^(+)和4^(2)Π,5^(2)Π态的主要电子组态成分随平衡核间距的变化.此外,还计算了PbBr基态X^(2)Π和第一激发态1^(2)Σ^(+)之间的跃迁性质,包括跃迁偶极矩(TDMs)和弗兰克-康登因子(FCFs).研究结果对PbBr分子电子结构和光谱性质后续的实验以及理论研究具有一定的参考价值.The electronic structure of PbBr molecules are calculated with the high-level multi-reference configuration interaction(MRCI)method.In order to ensure the accuracy of the calculation,Davidson correction(+Q)and core-valence(CV)electrons correlations effect are taken into account.Based on the calculated energies,potential energy curves(PECs)of 23LS-states corresponding to the three lowest dissociation limits of PbBr molecule are plotted.According to the calculated potential energy curves,the spectroscopic constants of the bound states are calculated,and the calculated results are in good agreement with the previous results.The dipole moment(DMs)ofLS-states are determined by configuration interaction method.In avoided crossing region,the DMs ofLS-states shows abrupt change,which can be attributed to the changes in the electronic structure of these states.The main electron configuration components of 2^(2)Σ^(+),3^(2)Σ^(+) and 4^(2)Π,5^(2)Πstates are plotted with the variation of bond length.In addition,the transition properties between the ground states X^(2)Π and the first excited state 1^(2)Σ^(+) of the PbBr,including transition dipole moments(TDMs)and Frank-Condon factors(FCFs)were calculated.The results have a certain reference value for the subsequent experiments and theoretical studies on the electronic structure and spectral properties of PbBr molecules.

关 键 词：Pb Br 势能曲线 光谱常数 跃迁性质 

分 类 号：O561[理学—原子与分子物理]