Al-Raeei Marwan
Faculty of Sciences, Damascus University, Damascus, Syrian Arab Republic.
BMC Chem. 2022 Mar 27;16(1):22. doi: 10.1186/s13065-022-00811-3.
The specific heat in its molar form or mass form is a significant thermal property in the study of the thermal capacity of the described system. There are two basic methods for the determination of the molar specific heat capacity, one of them is the experimental procedure and the other is the theoretical procedure. The present study deals with finding a formula of the molar specific heat capacity using the theory of the integral equations for Morse interaction which is a very important potential for the study of the general oscillations in the quantum mechanics. We use the approximation (Mean-Spherical) for finding the total energy of the compositions described by Morse interaction. We find two formulas of the heat capacity, one at a constant pressure and the other at a constant volume. We conclude that the Morse molar specific heat is temperature dependent via the inverse square low with respect to temperature. Besides, we find that the Morse molar specific heat is proportional to the square of the Morse interaction well depth. Also, we find that the Morse molar specific heat depends on the particles' diameter, the bond distance of Morse interaction, the width parameter of Morse interaction, and the volumetric density of the system. We apply the formula of the specific heat for finding the specific heat of the vibrational part for two dimer which are the lithium and caesium dimers and for the hydrogen fluoride, hydrogen chloride, nitrogen, and hydrogen molecules.
以摩尔形式或质量形式表示的比热容是研究所述系统热容量时的一个重要热性质。测定摩尔比热容有两种基本方法,其中一种是实验方法,另一种是理论方法。本研究致力于利用莫尔斯相互作用的积分方程理论来推导摩尔比热容的公式,莫尔斯相互作用对于量子力学中一般振动的研究是一种非常重要的势。我们使用(平均球近似)来求由莫尔斯相互作用描述的体系的总能量。我们得到了两个比热容公式,一个是定压比热容公式,另一个是定容比热容公式。我们得出结论,莫尔斯摩尔比热容通过与温度的平方反比关系依赖于温度。此外,我们发现莫尔斯摩尔比热容与莫尔斯相互作用势阱深度的平方成正比。而且,我们发现莫尔斯摩尔比热容取决于粒子直径、莫尔斯相互作用的键距、莫尔斯相互作用的宽度参数以及体系的体积密度。我们应用比热容公式来求锂二聚体、铯二聚体、氟化氢、氯化氢、氮气和氢分子这两种二聚体振动部分的比热容。