Simple systematization of structural stability for A(N)B(8-N) compounds

The structural stability of A(N)B(8-N) compounds such as GaAs, GaN, and NaCl is systematically investigated using our simple criterion on the basis of the ionicity, bond charge, and ionic charge of the A(N)B(8-N) compounds. The criterion implies that the wurtzite structure is more stable than the zinc blende structure when the ionicity is greater than 0.319 for N = 4 (group IV), 0.455 for N = 3 (III-V), 0.652 for N = 2 (II-VI), and 0.882 for N = 1 (I-VII compounds). Furthermore, the rocksalt structure is stabilized at ionicities greater than 0.479 for N = 4 (group IV), 0.620 for N = 3 (III-V), 0.786 for N = 2 (II-VI), and 0.936 for N = 1 (I-VII compounds). This simple criterion is successfully applied to predict the structural phase diagram of A(N)B(8-N) compounds as a function of ionicity and ionic charge.