Spectroscopy of Ar-SH and Ar-SD. II. Determination of the three-dimensional intermolecular potential-energy surface.
Spectroscopy of Ar-SH and Ar-SD. II. Determination of the three-dimensional intermolecular potential-energy surface.
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DOI：
10.1063/1.1943968
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发表时间：
2005-08
期刊：
影响因子：
--
通讯作者：
Y. Sumiyoshi;Y. Endo
中科院分区：
文献类型：
--
作者：
Y. Sumiyoshi;Y. Endo
以往研究报道的纯旋转跃迁[J]。化学。物理学报（英文版）；[J] .光谱学与光谱分析，2003,22(2):1 - 2 <—3/2。化学。理论物理。（2005），同时分析了前面的论文]，以确定Ar-SH在基态下的一个新的分子间势能面。采用离散变量表示方法，对考虑原子-硅藻配合物在雅可比坐标R、θ和R下三维运动自由度的薛定谔方程进行了数值求解，得到了旋转振动能级的能量。在理论的RCCSD(T)/ augg -cc- pvtz水平上，用从头算得到的势能参数的初值进行最小二乘拟合，确定了三维势能面。该势阱以宇称加倍和超细分裂再现了微波和毫米波区域的所有观测数据。利用新势能面计算了几种低洼的旋转振动能。讨论了Ar和SH之间的相互作用能（2 π (i)）与SH单体键长的关系。
All the pure rotational transitions reported in the previous studies [J. Chem. Phys. 113, 10121 (2000); J. Mol. Spectrosc. 222, 22 (2003)] and newly observed rotation-vibration transitions, P = 1/2 <-- 3/2, for Ar-SH and Ar-SD [J. Chem. Phys. (2005), the preceding paper] have been simultaneously analyzed to determine a new intermolecular potential-energy surface of Ar-SH in the ground state. A Schrodinger equation considering the three-dimensional freedom of motion for an atom-diatom complex in the Jacobi coordinate, R, theta, and r, was numerically solved to obtain energies of the rovibrational levels using the discrete variable representation method. A three-dimensional potential-energy surface is determined by a least-squares fitting with initial values of the parameters for the potential obtained by ab initio calculations at the RCCSD(T)/aug-cc-pVTZ level of theory. The potential well reproduces all the observed data in the microwave and millimeter wave regions with parity doublings and hyperfine splittings. Several low-lying rovibrational energies are calculated using the new potential-energy surface. The dependence of the interaction energy between Ar and SH(2pi(i)) on the bond length of the SH monomer is discussed.