Effect of iron substitution on the coordination properties of sphalerite

Abstract

In nature, when the Fe content is greater than 6 %, it is the most stable impurity in the sphalerite lattice. Fe dissolves in the mineral lattice in an isomorphous form, that is, it replaces Zn to form Fe-containing sphalerite, whose chemical formula is [ZnxFe(1-x)] S, which belongs to the isometric crystal system, has ionic-covalent chemical bonds, has the most negative formation energy, and is more stable than element-doped ZnS ore. The properties of sphalerite with different Fe contents vary greatly. In essence, the coordination between sphalerite and Fe is a galvanic effect. The surface crystal structure of sphalerite with different Fe contents changes, resulting in Fe-ZnS electron rearrangement. The defect at the S-site alters the ligand arrangement, leading to the formation of Fe-S bonds as it interacts with Fe. This results in modifications to the surface coordination behavior and the lattice spacing of sphalerite. Under the action of the tetrahedral field, the e orbital is a π orbital, and t₂ is both a σ orbital and a π orbital. Since Fe²⁺ has a pair of π electrons, the reactivity of Fe-containing sphalerite is increased. This discovery provides a theoretical basis for natural iron sphalerite as a mineral material.