The statistical thermodynamic model for the vibrational partition function with separated stretching and bending is developed. The model is studied on the example of $$\hbox {CO}_{2}$$ CO 2 molecule for temperature up to 20,000 K with the aim to describe efficient dissociation by deposition of energy mainly to the stretching modes of vibration. The observed separation of bending mode at lower temperatures suggest that it is possible to construct such kinetic model of plasma in which the high vibrational temperature of stretching and the low vibrational temperature of bending are obtained resulting in an efficient dissociation. In particular, the proposed model is extended to ideal-gas version where all the interactions between atoms are taken into account. The idea behind such approach is to eliminate contributions to partition functions stemming from non-interacting dissociated fragments of the molecule. The application areas of such partition functions are discussed and the full vibrational partition functions based on that model are compared with the known data.

中文翻译：

---

三原子系统拉伸的高温振动分配函数

建立了拉伸和弯曲分离的振动分配函数的统计热力学模型。该模型在 $$\hbox {CO}_{2}$$ CO 2 分子的示例上进行了研究，温度高达 20,000 K，目的是通过主要向振动的拉伸模式沉积能量来描述有效解离。在较低温度下观察到的弯曲模式的分离表明，可以构建这样的等离子体动力学模型，其中获得高的拉伸振动温度和低的弯曲振动温度，从而导致有效的解离。特别是，所提出的模型扩展到理想气体版本，其中考虑了原子之间的所有相互作用。这种方法背后的想法是消除对源自分子非相互作用解离片段的分配函数的贡献。讨论了这种分配函数的应用领域，并将基于该模型的完整振动分配函数与已知数据进行了比较。