Abstract Based on the improved Rosen-Morse oscillator for describing the internal vibration of a molecule, we establish an explicit representation of molar entropy for gaseous substances. Using the dissociation energy, equilibrium internuclear distance and harmonic vibrational frequency, we calculate the molar entropy values of the gaseous phosphorus dimer. Our calculated results show an excellent agreement compared to the experimental data in a wide variety of temperatures ranging from 298 up to 6000 K.

中文翻译：

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气态磷二聚体焓

摘要 基于改进的描述分子内部振动的Rosen-Morse振子，我们建立了气态物质摩尔熵的显式表示。使用解离能、平衡核间距离和谐波振动频率，我们计算气态磷二聚体的摩尔熵值。我们的计算结果与在 298 到 6000 K 范围内的各种温度下的实验数据相比显示出极好的一致性。