采用高精度的多参考组态相互作用方法计算了ZnH分子的能量最低四个离解限Zn(^1Sg)+H(^2Sg),Zn(^3P2u)+H(Sg),Zn^+(^2Sg)+H^-(^1Sg)和Zn(^1Pu)+H(^2Sg)对应的7个Λ-S态的势能曲线.计算中考虑了Davidson修正、标量相对论效应、自旋-轨道耦合效应和芯-价电子关联.基于计算的Λ-S和Ω态的势能曲线,数值求解一维径向Schrodinger方程得到了束缚电子态的光谱常数,理论计算结果与之前的实验结果符合较好.计算得到了7个Λ-S态的电偶极矩随核间距的变化曲线,分析了电子组态成分变化对电偶极矩和成键性质的影响.计算结果表明,C^2Σ^+态是一个离子对态.进一步地,分析了避免交叉点附近?态的Λ-S态组成的变化规律,讨论了避免交叉现象对跃迁偶极矩的影响.基于计算的跃迁偶极矩、Franck-Condon因子和振动能级信息,给出了束缚激发态(2)1/2,(3)1/2,(4)1/2和(1)3/2的v′=0—2振动能级的自发发射寿命,结果与现有实验值相符合.
The potential energy curves(PECs) associated with the lowest four dissociation limits,i.e.,Zn(^1Sg) + H(^2Sg),Zn(^3Pu)+H(^2Sg),Zn^+(^2S-2g)^+H^-(^1Sg) and Zn(^1Pu)+H(Sg),are calculated by using a high-level configuration interaction method.The Davidson correction,scalar relativistic effect and spin-orbit coupling effect are taken into account in calculation.On the basis of our calculated PECs of Λ-S and ? states,the spectroscopic constants including Te,ωe,ωeχ e,B e and R e are evaluated by numerical solution of one-dimensional Schr?dinger equation.The computed spectroscopic constants are reasonably consistent with previous experimental results.The dipole moment curves of the 7 Λ-S states are presented,and the influences of the variation of electronic configuration on the dipole moment and bonding property are discussed.The computational results reveal the ionic character of the C^2Σ^+state.The variation of Λ-S component for? state near the avoided crossing point is illuminated,which is used to explain the change of transition dipole moment(TDM) around the avoided crossing point.Based on the TDMs,Franck-Condon factors and the transition energies,the radiative lifetimes of v′= 0–2 vibrational levels of(2)1/2,(3)1/2,(4)1/2 and(1)3/2 states are predicted,which accord well with the available experimental values.