Anharmonic rovibrational numbers and densities of states for HO2, H2CO, and H2O2.
Anharmonic rovibrational numbers and densities of states for HO2, H2CO, and H2O2.
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HO2、H2CO 和 H2O2 的非简谐振动数和态密度。
DOI：
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发表时间：
2009
影响因子：
2.9
通讯作者：
V. Ushakov
中科院分区：
文献类型：
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作者：
Jürgen Troe;V. Ushakov
非谐振动数和态密度的计算量子校正的Monte Carlo积分的相空间体积从头计算的势能面为HO 2，H2 CO，和H2 O2。还确定了H2 CO的非谐性的旋转依赖性。态的总数W（E，J = 0）近似的解析形式。以Whitten-Rabinovitch公式为参考，解析地给出了态密度的非谐因子Fanh，rho（E，J = 0）。结果被用作与经验非谐性模型（Troe，J.Chem.Phys.1995，190，381）进行比较的基准。有人发现，这个模型的一些修改是必要的，在高能量的应用。改进的经验模型的目的是为估计在高能量的大分子系统的非谐态密度。
Anharmonic vibrational numbers and densities of states are calculated by quantum-corrected Monte Carlo integration of phase space volumes on ab initio potential energy surfaces for HO2, H2CO, and H2O2. Rotational dependences of the anharmonicity are also determined for H2CO. The total numbers of states W(E,J = 0) are approximated in analytical form. Using Whitten-Rabinovitch expressions as a reference, anharmonicity factors Fanh,rho(E,J = 0) for the densities of states are also given analytically. The results are used as a benchmark for comparisons with an empirical anharmonicity model (Troe, J. Chem. Phys. 1995, 190, 381). It was found that some modifications of this model are necessary for applications at high energies. The improved empirical model is intended to serve for estimates of anharmonic densities of states of larger molecular systems at high energies.