Study of α - Incommensurate - β transitions in quartz by white beam synchrotron radiation laue method

Abstract

The transitions between β, incommensurate (inc) and α phases of quartz have been investigated with the white beam Laue method, using synchrotron radiation. During the 1^rst order inc - α transition, inc satellites are observed to shift closer to the Bragg peak position. On the high temperature side, an intermediate phase with a 1q modulation exists in a small temperature interval of a few 0.01 K, between the usual 3q inc phase and the β phase. Several 1q domains have been directly observed by X-ray topography.