First observation of Ce volume collapse in CeN

TL;DR

This paper commemorates the 80th anniversary of Ce volume collapse in CeN, reviewing historical context, physical properties, and the significance of Ce as a mixed valence element, highlighting its impact on understanding Ce's valence instability.

Contribution

It provides a historical review of CeN's volume collapse and discusses the development of knowledge on Ce's valence instability over time.

Findings

Historical observation of Ce volume collapse in CeN

Review of Ce physical properties and valence behavior

Implications for understanding Ce's mixed valence nature

Abstract

On the occasion of the 80th anniversary of the first observation of Ce volume collapse in CeN a remembrance of the implications of that transcendent event is presented, along with a review of the knowledge of Ce physical properties available at that time. Coincident anniversary corresponds to the first proposal for Ce as a mix valence element, motivating to briefly review how the valence instability of Ce was investigated since that time.