Sumiyoshi Yoshihiro, Funahara Ippei, Sato Kazuya, Ohshima Yasuhiro, Endo Yasuki
Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan.
J Chem Phys. 2006 Sep 28;125(12):124307. doi: 10.1063/1.2353120.
Pure rotational transitions in the ground state for Ar-OH and Ar-OD [Y. Ohshima et al., J. Chem. Phys. 95, 7001 (1991) and Y. Endo et al., Faraday Discuss. 97, 341 (1994)], those in the excited states of the OH vibration, nu(s)=1 and 2, observed by Fourier-transform microwave spectroscopy in the present study, rotation-vibration transitions observed by infrared-ultraviolet double-resonance spectroscopy [K. M. Beck et al., Chem. Phys. Lett. 162, 203 (1989) and R. T. Bonn et al., J. Chem. Phys. 112, 4942 (2000)], and the P-level structure observed by stimulated emission pumping spectroscopy [M. T. Berry et al., Chem. Phys. Lett. 178, 301 (1991)] have been simultaneously analyzed to determine the potential energy surface of Ar-OH in the ground state. A Schrodinger equation, considering all the freedom of motions for an atom-diatom system in the Jacobi coordinate, R, theta, and r, was numerically solved to obtain energies of the rovibrational energy levels using the discrete variable representation method. A three-dimensional potential energy surface is determined by a least-squares fitting. In the analysis the potential parameters, obtained by ab initio calculations at the RCCSD(T) level of theory with a set of basis functions of aug-cc-pVTZ and midbond functions, are used as initial values. The determined intermolecular potential energy surface and its dependence on the OH monomer bond length are compared with those of an isovalent radical complex, Ar-SH.
Ar-OH和Ar-OD基态的纯转动跃迁[Y. Ohshima等人，《化学物理杂志》95, 7001 (1991)以及Y. Endo等人，《法拉第讨论》97, 341 (1994)]、本研究中通过傅里叶变换微波光谱观测到的OH振动激发态（ν(s)=1和2）的跃迁、通过红外-紫外双共振光谱观测到的转动-振动跃迁[K. M. Beck等人，《化学物理快报》162, 203 (1989)以及R. T. Bonn等人，《化学物理杂志》112, 4942 (2000)]以及通过受激发射泵浦光谱观测到的P能级结构[M. T. Berry等人，《化学物理快报》178, 301 (1991)]已被同时分析，以确定Ar-OH基态的势能面。在雅可比坐标R、θ和r中考虑原子-双原子系统所有运动自由度的薛定谔方程，使用离散变量表示法进行数值求解以获得振转能级的能量。通过最小二乘法拟合确定三维势能面。在分析中，将在RCCSD(T)理论水平上使用aug-cc-pVTZ基函数集和中间键函数进行从头计算得到的势能参数用作初始值。将确定的分子间势能面及其对OH单体键长的依赖性与等电子自由基复合物Ar-SH的进行比较。
