Phase Transitions without Thermodynamic Limit

TL;DR

This paper demonstrates how microcanonical statistics can analyze phase transitions in finite, non-extensive systems like atomic clusters without requiring the thermodynamic limit, revealing detailed transition mechanisms.

Contribution

It shows that microcanonical thermodynamics effectively studies phase transitions in finite systems, providing insights into transition temperature, latent heat, and surface entropy without thermodynamic limit assumptions.

Findings

Determines transition temperature, latent heat, and surface entropy for finite atomic systems.

Analyzes the development of phase transition mechanisms through energy control.

Applies microcanonical approach to systems of 200-3000 atoms at 1 atm.

Abstract

Microcanonical statistics can be well applied to non-extensive systems like nuclei, atomic clusters and systems at phase transitions of first order with inhomogeneous configurations like phase separation. No thermodynamic limit has to be invoked. It allows to determine the transition temperature, latent heat and surface entropy. In the present paper this is demonstrated for systems of 200 - 3000 Na-, K-, and Fe-atoms at 1 atmosphere. As the energy is an exactly conserved quantity it is a usefull control parameter to tune through the development of the transition from the liquid side of the coexistence region over the evaporation, multifragmentation towards the final gas side. Microcanonical thermodynamics thus resolves details of the mechanism leading to the phase transition.