Predicting synthesizable manganese nitride with unprecedentedly giant magnetocrystalline anisotropy energy

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.