Identity of electrons and ionization equilibrium

TL;DR

This paper revisits ionization equilibrium in gases, highlighting quantitative differences from the classical Saha formula due to the distinction between physical and chemical models of matter.

Contribution

It introduces a physical model for ionization in gases that reveals significant quantitative differences from the traditional Saha formula, emphasizing the importance of model choice.

Findings

Quantitative differences from Saha formula in ionization degree

Physical model aligns qualitatively but differs quantitatively

Highlights the distinction between physical and chemical models

Abstract

It is perhaps appropriate that, in a year marking the 90th anniversary of Meghnad Saha seminal paper (1920), new developments should call fresh attention to the problem of ionization equilibrium in gases. Ionization equilibrium is considered in the simplest "physical" model for an electronic subsystem of matter in a rarefied state, consisting of one localized electronic state in each nucleus and delocalized electronic states considered as free ones. It is shown that, despite the qualitative agreement, there is a significant quantitative difference from the results of applying the Saha formula to the degree of ionization. This is caused by the fact that the Saha formula corresponds to the "chemical" model of matter.