Kong Y.
In order to investigate the phase stability of equiatomic FeN compounds and the structure-dependent magnetic properties, the electronic structure and total energy of FeN with NaCl, ZnS and CsCl structures and various magnetic configurations are calculated using the first-principle TB-LMTO-ASA method. Among all the FeN phases considered, the antiferromagnetic (AFM) NaCl structure with a=4.33Å but for AFM NaCl phase the ^{exp}a=4.20Å is 6.7% smaller than the value observed experimentally. For ZnS-type FeN, metastable magnetic states are found for volumes larger than the equilibrium value. With the analysis of atom- and orbital-projected density of states (DOS) and orbital-resolved crystal orbital Hamilton population (COHP) the iron-nitrogen interactions in NM-ZnS, AFM-NaCl and FM-CsCl structures are discussed. The leading Fe-N interaction is due to the ^{th }d-p iron-nitrogen hybridization while considerable s-p and p-p hybridizations are also observed in all three phases. The iron magnetic moment m in FeN is found to be highly sensitive to the nearest-neighboring Fe-N distance. In particular, the _{Fe}m in ZnS and CsCl structures show an abrupt drop from the value of about 2_{Fe}m to zero with the reduction of the Fe-N distance. _{B} A reprint of this paper can be obtained
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