LiC分子基态及其低电子激发态的多参考组态相互作用方法研究

采用包含Davidson修正的多参考组态相互作用(MRCI+Q)方法结合6-311++G(3df,3pd)基组计算了LiC分子基态(X4Σ-)以及五个低电子激发态(a2Π,b2Δ,c2Σ-,d2Σ+,A4Π)的势能曲线.将得到的势能曲线拟合到Murrell-Sorbie解析势能函数形式,确定了对应态的平衡结构Re、谐振频率ωe和离解能De等光谱数据,计算值与仅有的几个其他结果进行了比较.通过求解核运动的薛定谔方程首次报道了LiC分子几个低电子态在J=0下的振动能级、转动惯量和六个离心畸变常数(Dν,Hν,Lν,Mν,Nν和Oν).

Multi-reference configuration interaction of the ground and low-lying excited states of LiC

The potential energy curves (PECs) for the ground electronic state X⁴Σ^-and five low-lying excited electronic states (a²Π, b²Δ, c²Σ^-, d²Σ⁺, A⁴Π) of LiC have been calculated using the multiconfiguration reference configuration interaction method including Davidson correction (MRCI+Q). And PECs were fitted to analytical Murrell-Sorbie potential function to deduce the spectroscopic parameters of equilibrium bond length R_e, rotation coupling constant ω_e, anharmonic constant ω_eχ_e, equilibrium rotation constant B_e and vibration-rotation coupling constant α_e. Those values were also compared with the other results currently available. By solving the radial Schrdinger equation of nuclear motion, the vibration levels, inertial rotation constant and six centrifugal distortion constants (D_ν, H_ν, L_ν, M_ν,N_ν,and O_ν) are reported for the first time.