Habit Changes of Sapphire Grown from PbO-PbF2 and MoO3-PbF2 Fluxes

摘要

Single crystals of Al2O3 (sapphire) were grown from both PbO-PbF2 and MoO3-PbF2 fluxes. Their habits varied from flat plates (PbF2-rich melts) to equidimensional crystals (PbO- or MoO3-rich melts). The primary growth planes on these crystals are basal planes (0001), first-order rhombs (10-11), and second-order rhombs (01-12). The habit change is interpreted on the basis of F(1-) crystal contamination and Pb(2+) surface adsorption. Possible ion species in the melt and their relative importance on crystal growth from these melt systems are discussed. (Author)