Long range Coulomb forces and the behaviour of the chemical potential of electrons in metals at a second order phase transition

TL;DR

This paper analyzes how long-range Coulomb forces influence the chemical potential of electrons in metals during second order phase transitions, revealing potential observable shifts in surface potential.

Contribution

It provides a thermodynamic framework including Coulomb effects to predict chemical potential behavior at phase transitions in metals.

Findings

Chemical potential can exhibit a kink at T_c.

Coulomb forces cause observable shifts in surface potential.

Behavior depends on fixed volume or pressure conditions.

Abstract

We give a general thermodynamic analyzis of the behaviour of the chemical potential of electrons in metals at a second order phase transition, including in our analysis the effect of long range Coulomb forces. It is shown, that this chemical potential can have a kink at T$_c$, both for fixed sample volume and fixed external pressure. The Coulomb term transfers the changes in chemical potential of the electrons into an experimentally observable shift of the surface potential if the sample is electrically connected to a ground potential. VSGD.93.9.th1