In this work, ab initio calculations on the low-lying electronic states of arsenic bromide (AsBr) have been carried out using the internally contracted multi-reference configuration interaction with the addition of Davidson correction (icMRCI+Q) method. The potential energy curves (PECs) of the 34 Λ-S states and the 74 Ω states generated from the Λ-S states after considering the spin-orbit coupling (SOC) effects are calculated. The spectroscopic constants of the typical bound states have been calculated and are compared with available experiment results. With the calculated spin-orbit matrix element we analyze the SOC-induced predissociation mechanisms of the a¹Δ and b¹Σ⁺ states. The permanent dipole moments (PDMs), transition dipole moments (TDMs), Frank-Condon factors (FCFs) and radiative lifetimes of some low-lying states have also been acquired, which would be of value to understand the transition properties. Our study should enhance our understanding on the electronic structure and spectroscopy of AsBr molecule.

在这项工作中，已经使用内部收缩的多参考构型相互作用以及添加的戴维森校正（icMRCI + Q）方法对溴化砷（AsBr）的低电子态进行了从头计算。在考虑了自旋轨道耦合（SOC）效应后，计算了34种Λ-S状态和74Ω状态的势能曲线（PEC）。已计算出典型结合态的光谱常数，并与可用的实验结果进行了比较。与计算出的自旋-轨道矩阵元素分析了一个的SOC诱导的预离解机制¹ Δ和b ¹ Σ ⁺状态。还获得了一些低洼状态的永久偶极矩（PDM），跃迁偶极矩（TDM），Frank-Condon因子（FCF）和辐射寿命，这对于理解跃迁特性很有用。我们的研究应增强我们对AsBr分子的电子结构和光谱的理解。