Predicting synthesizable manganese nitride with unprecedentedly giant magnetocrystalline anisotropy energy

TL;DR

This study uses crystal structure prediction to identify manganese nitride structures with unprecedentedly high magnetocrystalline anisotropy energy, highlighting their potential for advanced magnetic applications.

Contribution

The paper reports the discovery of multiple manganese nitride structures with giant and nearly perfect easy-axis MAE using modern crystal structure prediction methods.

Findings

MnN exhibits giant MAE with values over 900 ueV/atom.

Several Mn2N structures show almost perfect easy-axis MAE.

Multiple Mn4N structures have high MAE values, promising for further research.

Abstract

Using modern crystal structure prediction program (CALYPSO), we searched many experimentally synthesizable low-energy structures with perfect or nearly perfect easy-axis magnetocrystalline anisotropy energy (MAE) in manganese nitride, including MnN, Mn2N, Mn3N2, Mn5N2, Mn4N, respectively, which are the more frequently studied stoichiometries by experimental researchers. MnN ( I-42d) shows giant MAE with values of E001=1006, E010=0, E100=920 ueV/atom (same hereinafter), respectively. One perfect easy-axis MAE in Mn3N2 (P42/mmc) with correspondent values of E010=E100=12 is observed, the other nearly perfect easy-axis MAE one (Ibam) with respective values of E001=324 and E010=345 is observed. Four almost totally perfect easy-axis MAE structures are obtained in Mn2N, including P4/mmm with individual E001=249 and E100=250, Pccm with E001=E100=62, P4/nmm with E001=58 and E100=60, Imma with E001=108 and E100=109, respectively. Three structures including one perfect candidates are found in Mn4N, including Fmmm with individual E001=126 and E010=121, I4/mmm with E010=127 and E100=133, I4/mmm with E001= E100=169, respectively. Too many valuable structures are deserved to be further studied by both theoretical and experimental scientists. The present study might attract close attention to these several compounds.