Theory of domain structures and associated defects in the incommensurate phase of quartz

Abstract

Two distinct sets of domain walls having the same free energy are predicted to exist in quartz; each set has its own triangular domain structure, which differs in orientation from that of the other set, and this gives rise to the possibility of a macrodomain structure in quartz. The question of the nature of the interface between two macrodomains is raised. The various possibilities for connecting the domain walls in both sets together give rise to the possibility of a large number of different defect structures.