Kashchiev Dimo
Institute of Physical Chemistry, Bulgarian Academy of Sciences, ul. Acad. G. Bonchev 11, Sofia 1113, Bulgaria.
J Chem Phys. 2020 Sep 28;153(12):124509. doi: 10.1063/5.0021337.
In the framework of the Gibbs approach to nucleation thermodynamics, expressions are derived for the nucleation work, nucleus size, surface tension, and Gibbs-Tolman length in homogeneous single-component nucleation at a fixed temperature. These expressions are in terms of the experimentally controlled overpressure of the nucleating phase and are valid for the entire overpressure range, i.e., for nucleus of any size. Analysis of available data for bubble and droplet nucleation in Lennard-Jones fluid shows that the theory describes well the data by means of a single free parameter, the Gibbs-Tolman length of the planar liquid/vapor interface. It is found that this length is about one-tenth of the Lennard-Jones molecular-diameter parameter and that it is positive for the bubble nucleus and negative for the droplet nucleus. In a sufficiently narrow temperature range, the nucleation work, nucleus radius, scaled surface tension, and Gibbs-Tolman length are apparently universal functions of scaled overpressure.
在吉布斯成核热力学方法的框架内,推导了在固定温度下均相单组分成核过程中的成核功、核尺寸、表面张力和吉布斯 - 托尔曼长度的表达式。这些表达式是根据成核相的实验控制过压得出的,并且在整个过压范围内都有效,即适用于任何尺寸的核。对 Lennard-Jones 流体中气泡和液滴成核的现有数据进行分析表明,该理论通过一个单一的自由参数——平面液/气界面的吉布斯 - 托尔曼长度,很好地描述了这些数据。结果发现,这个长度约为 Lennard-Jones 分子直径参数的十分之一,并且对于气泡核为正,对于液滴核为负。在足够窄的温度范围内,成核功、核半径、标度化表面张力和吉布斯 - 托尔曼长度显然是标度过压的通用函数。