Effect of a Phase Transformation on the Vapor Phase Growth of Single-Crystal HgS

Abstract

Attempts have been made to grow single-crystal HgS using a vapor phase growth technique. The lack of success led to the discovery of a phase transformation which occurs between the temperature of deposition and room temperature. The crystals were deposited in the cubic meta-cinnabar form and transformed to the hexagonal cinnabar form upon cooling, with a resultant destruction of the deposited crystals. There is a large supercooling effect which seems to depend upon particle size. Upon heating cinnabar in an atmosphere of air the transformation to meta-cinnabar occurs at 335°±10°C. Possibilities for the use of other techniques in the growth of single-crystal HgS are considered.