Influence of 3d-Fe substitution on structural, mechanical, electronic, and magnetic properties in rock-salt SrS: Insights from the first-principles study

Abstract

In the present work, first-principles calculations are carried out to investigate the impact of strontium (Sr) replacement by iron (Fe) atoms on the structural, mechanical, electronic, and magnetic properties of rock-salt Sr1-xFexS (0.125≤x≤0.75) compounds. Our calculation results show that the non-magnetic semiconductor-to-ferromagnetic half-metal-to magnetic metal transition and the indirect-to-direct-to-indirect bandgap transition can be realized by altering the Fe concentration. Further analysis indicates that this alteration affects the half-metallic bandgaps, magnetic moments, and exchange constants. The induced ferromagnetism and half-metallicity are attributed to the p-d hybridization between 3d-Fe and 3p-S states. A mechanical study is performed, and it is found that all the titled compounds are mechanically stable. Meanwhile, the high ratio of bulk modulus to shear modulus (B/G) suggests that they are ductile. Finally, an evaluation of the Debye temperature and melting point reveals the potential for the examined compounds to be used in thermal applications.