Insight into the Magnetic Moment of Iron Borides: Theoretical Consideration from Local Coordinative and Electronic Environment
Experimentally observed magnetic properties are usually statistically averaged from bulk materials and information associated with local chemical environment can not be specified. Against the backdrop, we propose a theoretical strategy to provide in-depth understanding of multi-role for metrics may contribute to apparent magnetic moment of iron borides. In particular, we demonstrate this strategy through systematic manipulation of iron/boron stoichiometry of the six prototype iron borides to tune their associated local structural and electronic environment to further modulate resultant magnetic moment. The local coordinative structures of six iron borides were resolved utilizing bond valence analysis by taking different coordination shell into account. Furthermore, the local electronic properties of each Fe atom in these iron borides, such as charge transfer, electronic distribution, bonding feature and orbital energy level, were carefully analyzed by bader analysis, density of states and Crystal Orbital Hamilton Population. In combination of analyses from both coordinative and electronic properties of the prototype iron borides, a linear relationship between local magnetic moment and bond valence as well as average energy of Fe 3d orbital has been confirmed.