Identity of electrons and ionization equilibrium

¹ Joint Institute for High Temperatures, Russian Academy of Sciences - 13/19, Izhorskaia Str., Moscow 125412, Russia
² Institut für Physik, Humboldt-Universität zu Berlin - Newtonstraße 15, D-12489 Berlin, Germany, EU

^a satron@mail.ru

Received: 6 March 2011
Accepted: 30 May 2011

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. It is established that, according to the identity principle, the “physical” model with only one chemical potential for all electrons in the system should be used, in contrast with the Saha “chemical” approach. 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 the application of the Saha formula to the degree of ionization and chemical potential. This is caused by the fact that the Saha formula corresponds to the “chemical” model of matter.