Spectroscopic investigations on AlH(X¹Σ⁺) radical using multireference configuration interaction theory in combination with correlation‐consistent quintuple basis set augmented with diffuse functions

Abstract

ABSTRACT:The equilibrium internuclear separations, harmonic frequencies, and potential energy curves (PECs) of the AlH(X 1 R þ ) radical have been investigated using the , 0.18876 cm À1 , and 6.3663 cm À1 , respectively, which almost perfectly conform to the available measurements. With the potential determined at the MRCI/aug-cc-pV5Z level of theory, the total of 26 vibrational states is predicted when the rotational quantum number J is set to equal zero (J ¼ 0) by numerically solving the radial Schrö dinger equation of nuclear motion with the Numerov method. The complete vibrational levels, classical turning points, inertial rotation, and centrifugal distortion constants are determined when J ¼ 0 for the first time, which are in excellent agreement with the available experimental data.

The emission spectroscopy of AlD in the visible region: experimental and theoretical investigations

“…The aug-cc-pV5Z MRCI+SO calculation reported here underestimates the experimental [28] bond length of the X 1 Σ + state by 0.8 pm, a similar accuracy [55] to that demonstrated by Shi et al in their study of the ground state alone. The values of r e and T e were generated using a spline of the spin-orbit ab initio data.…”

Theoretical study on spectroscopic properties of 10 Λ-S and 26 Ω states for AlH molecule

“…其势阱深度为25669.75 cm -1 , 包 含26个振动态. 由表2可知, 本文计算的 R e , w e , B e 和D e 与实验值 [8][9][10][13][14][15]18] 吻合很好, 它们与实 验 值 [8][9][10][13][14][15]18] 的 最 大 偏 离 分 别 为 0.00051 nm (0.3096%), 1.49 cm -1 (0.0886%), 0.04195 cm -1 (0.6561%) 和0.0225 eV (0.7120%); 仅文献 [25,[27][28][29][30][31]中的 R e 值、文献 [23,29,30]中的w e 值、文献 [23,25,27,28,30]中的B e 值和文献 [22,23,28,31]中的 D e 值与实验值 [8−10, 13−15, 18] 的最大偏离稍微小于 本文的结果.…”

“…Wells和Lane [6] , Woon和Dunning [22] 以及Shi等 [23] 利用多参考组态相互作用(MRCI)方法和相关一 致基组计算了AlH分子基态(X 1 S + [6,22,23] )和激发 态(a 3 P, A 1 P, 1 3 S + , b 3 S -, 2 3 S + , 2 3 P, C 1 S + , 1 5 S -和1 5 P) [6] 的势能曲线, 并报道了束缚的单重态和 三重态的部分光谱常数、A 1 P 和a 3 P态到 X 1 S + 态 跃迁P(1)支的波数和Franck-Condon因子 [6] 、并 基于A 1 P→X 1 S + 跃迁对角化的Franck-Condon因 子研究了激光冷却AlH分子的可行性 [6] . Tao等 [20] 利用内收缩(ic)的icMRCI/aug-cc-pV5Z(AV5Z) 理论计算了X 1 S + , a 3 P, 1 3 S + , b 3 S -, 2 3 S + 和C 1 S + 的势能曲线、1 3 S + 和b 3 S -态之间的自旋-轨道耦合 矩阵元, 并报道了X 1 S + , a 3 P和b 3 S -态u = 0能…”