The Analytical Theory of Bulk Melting II: Variational Method Solution in the FCC Crystal

TL;DR

This paper develops a variational method to model the temperature-dependent behavior of interstitial defects in FCC crystals, revealing that defect avalanche triggers melting, linking Lindemann and Born criteria.

Contribution

It introduces a variational approach to analyze defect-driven melting in FCC crystals, providing a theoretical framework connecting defect instability to melting criteria.

Findings

Interstitial defect avalanche causes melting instability

The model links Lindemann and Born criteria for melting

Provides a temperature-dependent free energy analysis

Abstract

Continuing the arguments in Paper I (arXiv: cond-mat/0405487), we model the temperature dependence of interstitial defects in a surface-free face-centered-cubic (fcc) elemental crystal and obtain the free energy and correlation behavior based on variational methods. We show that the avalanche of interstitial defects is the instability mechanism at the melting point that bridges Lindemann and Born criteria.