Gopakumar Geetha, Abe Minori, Hada Masahiko, Kajita Masatoshi
Department of Chemistry, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan.
National Institute of Information and Communications Technology, Koganei, Tokyo 184-8795, Japan.
J Chem Phys. 2014 Jun 14;140(22):224303. doi: 10.1063/1.4881396.
Electronic open-shell ground-state properties of selected alkali-metal-alkaline-earth-metal polar molecules are investigated. We determine potential energy curves of the (2)Σ(+) ground state at the coupled-cluster singles and doubles with partial triples (CCSD(T)) level of electron correlation. Calculated spectroscopic constants for the isotopes ((23)Na, (39)K, (85)Rb)-((40)Ca, (88)Sr) are compared with available theoretical and experimental results. The variation of the permanent dipole moment (PDM), average dipole polarizability, and polarizability anisotropy with internuclear distance is determined using finite-field perturbation theory at the CCSD(T) level. Owing to moderate PDM (KCa: 1.67 D, RbCa: 1.75 D, KSr: 1.27 D, RbSr: 1.41 D) and large polarizability anisotropy (KCa: 566 a.u., RbCa: 604 a.u., KSr: 574 a.u., RbSr: 615 a.u.), KCa, RbCa, KSr, and RbSr are potential candidates for alignment and orientation in combined intense laser and external static electric fields.
研究了选定的碱金属 - 碱土金属极性分子的电子开壳层基态性质。我们在包含部分三重激发的耦合簇单双激发（CCSD(T)）电子相关水平下确定了(2)Σ(+)基态的势能曲线。将计算得到的同位素（(23)Na、(39)K、(85)Rb）-（(40)Ca、(88)Sr）的光谱常数与现有的理论和实验结果进行了比较。在CCSD(T)水平下使用有限场微扰理论确定了永久偶极矩（PDM）、平均偶极极化率和极化率各向异性随核间距的变化。由于具有适度的PDM（KCa：1.67 D，RbCa：1.75 D，KSr：1.27 D，RbSr：1.41 D）和较大的极化率各向异性（KCa：566 a.u.，RbCa：604 a.u.，KSr：574 a.u.，RbSr：615 a.u.），KCa、RbCa、KSr和RbSr是在强激光和外部静电场组合中进行取向和排列的潜在候选分子。
