基于ab initio计算的氢化硼光谱性质理论研究  

Theoretical Study of Spectral Properties of Boron Hydride Based on ab Initio Calculation

作　　者：田亚莉 赵玉洁[1] 刘铭婕 和小虎 宫廷[1] 孙小聪 周月婷 郭古青 邱选兵 Andrey K.Belyaev[3] 李传亮 TIAN Ya-li;ZHAO Yu-jie;LIU Ming-jie;HE Xiao-hu;GONG Ting;SUN Xiao-cong;ZHOU Yue-ting;GUO Gu-qing;QIU Xuan-bing;Andrey K.Belyaev;LI Chuan-liang(Shanxi Province Engineering Research Center of Precision Measurement and Online Detection Equipment,Shanxi Center of Technology Innovation for Light Manipulations and Applications,School of Applied Science,Taiyuan University of Science and Technology,Taiyuan 030024,China;State Key Laboratory of Quantum Optics and Quantum Optics Devices,Shanxi University,Taiyuan 030006,China;Herzen State Pedagogical University of Russia,Petersburg 191186,Russia)

机构地区：[1]太原科技大学应用科学学院,山西省精密测量与在线检测装备工程研究中心,山西省光场调控与融合应用技术创新中心,山西太原030024 [2]山西大学量子光学与光量子器件国家重点实验室,山西太原030006 [3]Herzen State Pedagogical University of Russia,Petersburg,191186

出　　处：《量子光学学报》2024年第3期70-81,共12页Journal of Quantum Optics

基　　金：国家重点研发计划(2023YFF0718100);国家自然科学基金(52076145,12304403);山西省科技创新人才团队专项资助(202304051001034);山西省重点研发计划(202302150101017);山西省留学人员科技活动项目(20230031);山西省省筹资金资助回国留学人员科研资助项目(2023-151);山西省基础研究计划(202303021221147,202203021222204,202303021212224);山西省科技合作交流专项(202304041101022);江准前沿技术协同创新中心追梦基金课题(2023-ZM01C002);量子光学与光量子器件国家重点实验室开放课题(KF202305);太原科技大学科研启动基金(20222121,20232033);山西省科研实践创新类项目(2023KY667)。

摘　　要：本文针对BH分子的硼同位素(^(10,11)BH)的三个解离通道,深入探讨了其低能电子态的特性。为了获取BH分子精确的光谱数据,采用完全活性空间自洽场方法(CASSCF)和多参考组态相互作用结合戴维森修正(MRCI+Q)方法。推导并分析了势能曲线、电子组态及固有偶极矩,同时首次计算了1BH的部分激发态光谱常数,为理解该分子的电子结构提供了新的视角。此外,通过求解核运动的径向Schrodinger方程,得到了相应电子态的振-转光谱常数。为全面理解BH分子的跃迁性质,计算了跃迁偶极矩、Franck-Condon因子、振动分支比以及A^(1)П态的辐射寿命等关键参数,并详细分析了^(11)BH分子A^(1)П态的预解离机理。这些计算结果表明,^(11)BH分子具有成为多普勒激光冷却候选者的潜力。因此,我们进一步提出了使用A^(1)П(ν′)-X^(1)∑^(+)(ν″)跃迁进行激光冷却的方案。这一跃迁具有高度对角线的F-C因子(f_(00)=0.9991)和较短的辐射寿命(τ_(00)=124.23ns),是实现激光冷却的理想选择。本文设计了波长为432.48nm的主激光驱动冷却循环方案,预期可将BH分子冷却至微开尔文数量级的温度。通过对BH分子光谱行为的深入理解,有望在未来实现更高精度、更高效的分子激光冷却技术,推动超冷分子物理领域的研究取得新的突破。Objective The ab initio calculation method is based on the basic principles of quantum mechanics.Its essence lies in its independence from experimental data or empirical parameters,relying instead on theoretical derivations and computations to directly probe into the electronic structure and associated properties of molecules.This approach is pivotal for gaining an in-depth understanding of molecular structures and properties.When the accuracy of the calculations is utmost,the multi-reference configuration interaction(MRCI)method is favored due to its unique advantage of specifically considering strong interactions between multiple reference states.This feature is crucial for accurately describing complex electronic structures in molecular systems.Method The spectroscopic properties of the BH molecule have been thoroughly investigated.To correct for size inconsistency and enhance the accuracy of the calculations,an initial approximation of the electronic wave function is made using the Hartree-Fock method,then optimized using the state-averaged fully active space self-consistent field method,followed by the application of the multi-reference group state interaction method combined with the Davidson correction.On this basis,the spectral parameters of the electronic states are obtained by solving the one-dimensional radial Schrodinger equation for nuclear motion using the LEVEL program.The MOLPRO software package is employed to calculate the transition dipole moments of the A^(1)П(ν′)-X^(1)∑^(+)states.parameters such as the Franck-Condon factor and the Einstein A factor are obtained by fitting using the LEVEL program.Additionally,the radiative lifetimes between vibrational-rotational energy levels are calculated.Ultimately,candidate scheme for laser cooling of BH molecules are identified.Results and discussions The results provide the potential energy curves for the ten A-S states corresponding to the three dissociation limits of the BH molecule,as well as the spectroscopic constants of the bound-electron sta

关 键 词：氢化硼 多参考组态相互作用 光谱常数 辐射寿命 激光冷却 

分 类 号：O561.3[理学—原子与分子物理]