Tetrahedral covalent radii of Mn, Fe, Co and Ni estimated from extended X-ray absorption fine structure studies

The bond radius of an atom in a solid is an important parameter since it remains simply correlated with the bond length in a local coordination of the particular crystal structure. The tetrahedral covalent radii of Mn, Fe, Co and Ni were estimated from the measurements of their K-edge extended X-ray absorption fine structure in Zn1−xMxS (M=Mn, Fe, Co, Ni) alloys. Analysis of these data provided us with the bond lengths of both cationic species (Zn and M) with sulphur. The advantage of the common anion and the knowledge of the tetrahedral radius of Zn enabled us to derive the tetrahedral covalent radii of the transition metals studied.