Shumovskyi Nikolay A, Longo Thomas J, Buldyrev Sergey V, Anisimov Mikhail A
Department of Physics, Boston University, Boston, Massachusetts 02215, USA.
Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA.
Phys Rev E. 2022 Jul;106(1-2):015305. doi: 10.1103/PhysRevE.106.015305.
We suggest a simple model to describe polyamorphism in single-component fluids using a maximum-valence approach. The model contains three types of interactions: (i) Atoms attract each other by van der Waals forces that generate a liquid-gas transition at low pressures, (ii) atoms may form covalent bonds that induce association, and (iii) atoms with maximal valence attract or repel each other stronger than other atoms, thus generating liquid-liquid separation. As an example, we qualitatively compare this model with the behavior of liquid sulfur and show that condition (iii) generates a liquid-liquid phase transition in addition to the liquid-gas phase transition.
我们提出了一个简单的模型，用最高价方法来描述单组分流体中的多晶型现象。该模型包含三种相互作用：(i) 原子通过范德华力相互吸引，在低压下产生液-气转变；(ii) 原子可能形成共价键从而引发缔合；(iii) 具有最高价的原子比其他原子相互吸引或排斥得更强，从而产生液-液分离。作为一个例子，我们定性地将该模型与液态硫的行为进行比较，结果表明条件(iii)除了产生液-气相变外，还会产生液-液相变。
