Diffusion Monte Carlo calculations on LaB molecule

查看全文 作　　者：Nagat [1]Elkahwagy;Atif [1,2]Ismail;S M A [3]Maizet;K R [1]Mahmoud 机构地区：[1]Department of Physics, Faculty of Science, Kafrelsheikh University, Kafr El-Sheikh, Egypt;[2]Department of Physics, Faculty of Applied Sciences, Umm AI Qura University, Makkah, Saudi Arabia;[3]Department of Physics, Faculty of Science, Menoufia University, Shebin EI-Kom, Egypt 出　　处：《Chinese Physics B》索引2018年第27卷第9期,共6页 摘　　要：Potential energy curves for the lowest electronic states of LaB and LaB^- have been calculated by ab initio calculations.The diffusion Monte Carlo method has been employed in combination with three different trial functions. Spectroscopic constants have also been numerically derived for the neutral molecule and compared with the only available theoretical work;^([19]) however, predictions are provided for the corresponding constants for the anionic species which have not been reported yet. Our calculations suggest the high spin quintet state of LaB as the ground state with the triplet state higher in energy irrespective of the type of the functional used. This suggestion is in good accordance with the previous theoretical results calculated at B3LYP/LANL2DZ level of theory, whereas it contradicts with the prediction based upon B3LYP/SDD calculations in the same study. Moreover, variations of the permanent dipole moments as a function of the internuclear separations for the two electronic states of the neutral molecule have been studied and analyzed. 关 键 词：蒙特卡罗计算 实验室 分子 电子状态 INITIO 势能曲线 功能使用 数字地