Hill plot focusing on Ce compounds with high magnetic-ordering-temperatures and consequent study of Ce2AuP3

TL;DR

This study revisits the Hill plot for Ce compounds, revealing that high magnetic-ordering temperatures require short Ce-Ce distances and stable valence states, exemplified by Ce2AuP3 with a Curie temperature of 31 K.

Contribution

It provides a comprehensive analysis of Ce compounds' magnetic properties using a large database, highlighting the relationship between Ce-Ce distance and magnetic ordering temperature, and investigates Ce2AuP3's magnetic characteristics.

Findings

High magnetic-ordering temperatures in Ce compounds correlate with short Ce-Ce distances.

Ce2AuP3 exhibits a Curie temperature of 31 K and ferromagnetic behavior.

Doping may enhance magnetic anisotropy energy in Ce2AuP3.

Abstract

Hill plot is a well-known criterion of the f-electron element interatomic threshold-distance separating the nonmagnetic state from the magnetic one in actinides or lanthanides. We have reinvestigated the Hill plot of Ce compounds using a commercial crystallographic database CRYSTMET, focusing on a relationship between the Ce-Ce distance and the magnetic ordering temperature, because a Ce compound with no other magnetic elements scarcely has a magnetic ordering temperature higher than 20 K. The Hill plot of approximately 730 compounds has revealed that a Ce compound, especially for ferromagnet, showing the high magnetic-ordering-temperature would require a short Ce-Ce distance with a suppression of valence instability of Ce ion. Through the study, we had interest in Ce2AuP3 with the Curie temperature of 31 K. The ferromagnetic nature has been examined by a doping effect, which suggests a possible increase of magnetic anisotropy energy.