The present study is aimed at numerical simulation of the properties of iron nitride by mean of ab initio method. In the numerical computation, the crystal structure of the ’-Fe4N is built in form of an unit cell with a face-center cubic (FCC) Fe atoms structure containing one nitrogen atom placed at the crystal center. The experimental lattice constant, 3.790Å, has been used in this calculation, which is obtained from the on ab initio electronic structure methods derived from spin polarized density function theory (DFT). Meanwhile, results show that when the lattice parameter is increased, the magnetic moment of Fe-II is increased, while the magnetic moment of Fe-I is nearly unchanged. In addition, mechanical properties such as elastic constant and bulk modulus as well as thermal properties of iron nitride are also predicted. In this study, the chemical bond between Fe atoms and N atoms can be observed based on the predicted distribution of electron density.

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