Quantum assignments are reported for 1382 transitions towards 33 vibrational sub-levels belonging to three weak Triacontad bands 6ν, ν+5ν, ν+4ν of CH 1.28µm. Empirical values of the origins of the corresponded sub-bands were determined for the first time from high resolution spectra analysis. The positions of all assigned lines were fitted to a model adopting an effective Hamiltonian whose initial values are derived from the molecular potential energy surface by using the contact transformation method. An empirical optimization of this effective model resulted in the root-means-square deviation of 0.006 cm for newly assigned transitions. A comparison with variational ab initio calculations is discussed.

中文翻译：

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12CH4 的 6ν4、ν2+5ν4 和 ν1+4ν4 Triacontad 能带系统在 7606-7919 cm−1 区域的首次指配


报告了 1382 个跃迁到属于 CH 1.28μm 的三个弱三角带 6ν、ν+5ν、ν+4ν 的 33 个振动子能级的量子分配。首次通过高分辨率光谱分析确定了相应子带起源的经验值。所有指定线的位置均采用有效哈密顿量模型进行拟合，其初始值通过接触变换方法从分子势能面导出。该有效模型的经验优化导致新分配的跃迁的均方根偏差为 0.006 cm。讨论了与变分从头计算的比较。