Defect characterization of flux-grown GdCrO3 single crystals by scanning electron microscopy and energy dispersive spectroscopy

Abstract

Results of scanning electron microscopic and energy dispersive X-ray spectroscopic studies conducted on the defect structures exhibited by the virgin surfaces (habit faces) of single crystals of GdCrO3 and on the microstructures of the polished surfaces of these crystals grown from a PbO-PbF2 flux, are described. Some typical surface microstructures observed on the virgin surfaces are elliptical networks, ridges and furrows, microcrystals, inclusions and irregular microelevations. The stoichiometry of the elements of GdCrO3 across some microareas is disturbed. Energy dispersive analyses of virgin and polished surfaces of GdCrO3 crystals reveal the precipitation of lead compounds as secondary phases. The presence of other contaminants like Al and Si also appears in the energy spectrum. Crystallization and/or precipitation of secondary phases, including Pb2CrO5 and Pb2OF2 (undissolved flux), during the flux growth of the major phase GdCrO3, is discussed.