Equilibrium macroscopic structure revisited from spatial constraint

TL;DR

This paper reveals that in disordered equilibrium states, the macroscopic structure is uniquely determined by spatial constraints and is independent of temperature and interactions, enabling efficient prediction and analysis.

Contribution

It introduces a novel understanding that equilibrium structures depend solely on spatial constraints, allowing systematic prediction and interaction determination.

Findings

Equilibrium structures depend only on spatial constraints in disordered states.

The method enables efficient prediction of structures in multicomponent systems.

It allows accurate determination of multibody interactions from macroscopic data.

Abstract

In classical systems, we reexamine how macroscopic structures in equilibrium state connect with spatial con- straint on the systems: e.g., volume and density as the constraint for liquids in rigid box, and crystal lattice as the constraint for crystalline solids. We reveal that in disordered states, equilibrium macroscopic structure, depend- ing on temperature and on multibody interactions in the system, is characterized by a single special microscopic structure independent of temperature and of interactions. The special microscopic structure depends only on the spatial constraint. We demonstrate the present findings providing (i) significantly efficient and systematic prediction of macroscopic structures for possible combination of constituents in multicomponent systems, and (ii) unique and accurate determination of multibody interactions in given system from measured macroscopic structure, without performing trial-and-error simulation.