First-principles prediction of the electronic, magnetic and optical properties of N, P, As-doped marcasite FeS2

Abstract

Using the first-principles calculations, the electronic, magnetic and optical properties of non-metal (N, P or As) doped marcasite FeS2 (m-FeS2) have been investigated. It is feasible to combine N, P or As atoms into m-FeS2 experimentally under Fe-rich condition due to the negative formation energies. The spin stability calculations indicate that the three doped systems prefer spin polarized state. The substitutional doping of the N, P or As atom at S site can induce magnetism in m-FeS2 and the total magnetic moments of the three doped systems are all nearly 1μB, this is caused by one hole introduced by the dopants. Both N- and P-doped m-FeS2 systems show spin-gapless character while As-doped m-FeS2 system exhibits half-metallic feature. In addition, compared with the pristine m-FeS2, the P- or As-doped m-FeS2 systems have not only an enhanced absorption coefficient but also a red shift phenomenon. So the P- or As-doped m-FeS2 systems can be used in optoelectronic device.