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Ferromagnetic Half-Metal Cyanamides Cr(NCN)2 Predicted from First Principles Investigation.

ABSTRACT: The stability, physical properties, and electronic structures of Cr(NCN)2 were studied using density functional theory with explicit electronic correlation (GGA+U). The calculated results indicate that Cr(NCN)2 is a ferromagnetic and half-metal, both thermodynamically and elastically stable. A comparative study on the electronic structures of Cr(NCN)2 and CrO2 shows that the Cr atoms in both compounds are in one crystallographically equivalent site, with an ideal 4+ valence state. In CrO2, the Cr atoms at the corner and center sites have different magnetic moments and orbital occupancies, moreover, there is a large difference between the intra- (12.1 meV) and inter-chain (31.2 meV) magnetic couplings, which is significantly weakened by C atoms in Cr(NCN)2.

SUBMITTER: Wang Z

PROVIDER: S-EPMC7216073 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Ferromagnetic Half-Metal Cyanamides Cr(NCN)2 Predicted from First Principles Investigation.

Wang Zhilue Z Qu Shoujiang S Xiang Hongping H He Zhangzhen Z Shen Jun J

Materials (Basel, Switzerland) 20200411 8

The stability, physical properties, and electronic structures of Cr(NCN)2 were studied using density functional theory with explicit electronic correlation (GGA+U). The calculated results indicate that Cr(NCN)2 is a ferromagnetic and half-metal, both thermodynamically and elastically stable. A comparative study on the electronic structures of Cr(NCN)2 and CrO2 shows that the Cr atoms in both compounds are in one crystallographically equivalent s ...[more]

PMID: 32290419

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