Anion ordering in alkali cyanide crystals

Further molecular dynamics calculations have been carried out on sodium, potassium, and rubidium cyanides in their orientationally disordered cubic (Fm3m) phase. Simple, computationally efficient, rigid ion potentials are found to account for the overall range of static and dynamic properties. However, minor but systematic variations are required in the anion charge distribution. These changes mean that the charge distribution becomes more spherical as the size of the cation increases.