Shirin Sergei V, Zobov Nikolay F, Ovsyannikov Roman I, Polyansky Oleg L, Tennyson Jonathan
Institute of Applied Physics, Russian Academy of Sciences, Uljanov Street 46, Nizhny Novgorod 603950, Russia.
J Chem Phys. 2008 Jun 14;128(22):224306. doi: 10.1063/1.2927903.
Line lists of vibration-rotation transitions for the H(2) (16)O, H(2) (17)O, and H(2) (18)O isotopologues of the water molecule are calculated, which cover the frequency region of 0-20 000 cm(-1) and with rotational states up to J=20 (J=30 for H(2) (16)O). These variational calculations are based on a new semitheoretical potential energy surface obtained by morphing a high accuracy ab initio potential using experimental energy levels. This potential reproduces the energy levels with J=0, 2, and 5 used in the fit with a standard deviation of 0.025 cm(-1). Linestrengths are obtained using an ab initio dipole moment surface. That these line lists make an excellent starting point for spectroscopic modeling and analysis of rotation-vibration spectra is demonstrated by comparison with recent measurements of Lisak and Hodges [J. Mol. Spectrosc. (unpublished)]: assignments are given for the seven unassigned transitions and the intensity of the strong lines are reproduced to with 3%. It is suggested that the present procedure may be a better route to reliable line intensities than laboratory measurements.
计算了水分子的H₂¹⁶O、H₂¹⁷O和H₂¹⁸O同位素异构体的振动 - 转动跃迁谱线表，其覆盖0 - 20000 cm⁻¹频率范围，转动量子数J最高到J = 20（对于H₂¹⁶O为J = 30）。这些变分计算基于通过用实验能级对高精度从头算势能进行变形得到的新半理论势能面。该势能在拟合中重现了J = 0、2和5的能级，标准差为0.025 cm⁻¹。谱线强度通过从头算偶极矩面获得。与Lisak和Hodges [《分子光谱学杂志》（未发表）]最近的测量结果比较表明，这些谱线表是转动 - 振动光谱的光谱建模和分析的绝佳起点：给出了七条未归属跃迁的归属，并且强线强度的重现精度达到3%。有人认为，与实验室测量相比，本方法可能是获得可靠谱线强度的更好途径。
