SINGLE CRYSTALS MeO-MgO GROWTH AND PHASE TRANSFORMATION

摘要

Me_cMg_(1-c)O single crystals, where Me = Ni, Co, Mn have been grown by chemical transport reaction method (also known as sandwich method). It has been established that solid solution single crystals of Me_cMg_(1-c)O grown from polycrystalline solid solutions have NaCI type structure, substrate orientation and are monophase. The single crystals grown from nonstoichiometric polycrystalline source have the spinel phase inclusions. The mechanism of chemical transport reaction is established on the basis of thermodynamical calculation and experimental results of the MeO-MgO solid solution single crystal's growth. It is concluded that we must take into consideration the chemical activity of oxides estimated from the interaction energy.