The electronic structure of iron hydride Original Research Article

The electronic and bonding properties of iron monohydride were studied using qualitative electronic structure calculations in the framework of the extended hückel tight-binding method. The calculations were performed for a double hexagonal closed-packed structure for the hydride with the hydrogen atoms occupying the octahedral sites. The results were compared with pure hcp Fe and fcc Fe. Analysis of the orbital interaction reveals that H–Fe bonding involves mainly Fe 4s and H 1s orbitals. All s, p and d bands of the FeH present an energy gap at about −12.2 eV. The gap is larger for the p band. The overlap population between Fe atoms is considerably smaller in the hydride than in pure Fe.