X-ray absorption near-edge structure spectroscopy research on electronic structures and magnetic properties of (Fe 1- x Ni x ) 2 P

The Fe 2 P, Ni 2 P and (Fe 1- x Ni x ) 2 P compounds ( x =01,025,05) are studied by X-ray absorption near- edge structure (XANES) spectroscopy at the Fe, Ni and P K -edges. Combined with full multiple-scattering approach calculations of XANES, different contributions of 3f, 3g crystallographic positions to XANES spectra for metal atoms are discussed. It was found that the Ni atom prefers to substitute Fe (3f) sites when introducing Ni atoms. The first-principle density of states calculations were performed and the results show that unoccupied P p-projected DOS of paramagnetic Fe 2 P and Ni 2 P are matched with their K -edges XANES spectroscopy. Comparison with DOS calculations for ferromagnetic Fe 2 P, indicates that the magnetism of Fe 2 P is mostly due to Fe(3g) sites. The magnetic moments calculated for Ni(3f) and Ni(3g) sites of ferromagnetic Ni 2 P approach zero, which is in accordance with the conclusion that Ni 2 P generally appears paramagnetic.