Institute of Molecular Physics, Polish Academy of Sciences, M. Smoluchowskiego 17, 60-179 Poznań, Poland.
Department of Physics, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom.
Phys Rev E. 2018 Feb;97(2-1):022119. doi: 10.1103/PhysRevE.97.022119.
The influence of the strength of repulsion between particles on the thermodynamic curvature scalar R for the fluid and solid states is investigated for particles interacting with the inverse power (r^{-n}) potential, where r is the pair separation and 1/n is the softness. Exact results are obtained for R in certain limiting cases, and the R behavior determined for the systems in the fluid and solid phases. It is found that in such systems the thermodynamic curvature can be positive for very soft particles, negative for steeply repulsive (or large n) particles across almost the entire density range, and can change sign between negative and positive at a certain density. The relationship between R and the form of the interaction potential is more complex than previously suggested, and it may be that R is an indicator of the relative importance of energy and entropy contributions to the thermodynamic properties of the system.
研究了粒子间斥力强度对流体和固体状态下的热力学曲率标量 R 的影响，所研究的粒子相互作用采用的是反幂（r^{-n}）势，其中 r 是对间距，1/n 是软度。在某些极限情况下得到了 R 的精确结果，并确定了系统在流体相和固体相中的 R 行为。结果发现，在这种系统中，热力学曲率对于非常软的粒子可以是正的，对于急剧排斥（或大 n）的粒子在几乎整个密度范围内可以是负的，并且在某个密度处可以在负和正之间改变符号。R 与相互作用势能形式之间的关系比以前提出的更为复杂，可能 R 是能量和熵对系统热力学性质的贡献的相对重要性的一个指标。
