Accurate bond-valence parameters for the Bi³⁺/Br^- ion pair

Using a new calculation scheme, reliable and physically meaningful values of the bond-valence parameters (r₀ = 2.567 Å and b = 0.421 Å) have been deduced for the Bi³⁺/Br^- ion pair from the molecular geometry and from the crystal structure of BiBr₃.