Preferred Orientation of B2-Type Rb and K Halides in the Change B1 →B2-Type

Abstract

Rubidium and potassium halides (RbX and KX; X=F, Cl, Br and I except for RbF) retain preferred orientation of (100)(B2)//(111)(B1) and (111)/(B2)//(100)(B1) at the phase transition from B1 to B2-type structure under pressure. Geometry is shown for the movements of lattice points which are compatible with the orientation relation.