Determination of diatomic crystal bond lengths using atomics-orbital radii

We develop a theory to determine the bond lengths of over 270 AB crystals having ZnS, NaCl, and CsCl structures, including intermetallic compounds. The first-principles pseudopotential s-orbital radius rₛ is used, which contains no element-specific adjustable parameters. The good agreement found here between the calculated and measured bond lengths, along with the earlier successful applications of orbital radii for separating structures, illustrates the importance and usefulness of the orbital-radii scheme.