METHOD OF GROWING MONOCRYSTALS OF LITHIUM FERROSPINEL Russian patent published in 1997 - IPC

FIELD: inorganic synthesis. SUBSTANCE: invention relates to crystals applicable to devices based on magnetic excitements. 17.1-18.0 wt % boron oxide is melted in a crucible with 52.0-53.5 wt % bismuth(III) oxide, 17.2-18.0 wt % lithium carbonate, and ferric oxide (balance). Solution-melt is heated to 980-1000 C, then temperature gradient is established with vertical constituent 1-3 C (temperature lowers with distance from crucible bottom) and the solution-melt is maintained at this temperature for 20-24 h, 4-6 h of them under stirring. At a temperature exceeding saturation temperature by 5-10 C, melt is brought in contact with horizontally oriented surfaces of inoculations. Crystal carrier with inoculations is rotated with velocity 40-60 rpm. 20-30 min later temperature is lowered 5-7 C below saturation temperature and further according to program with increasing cooling velocity from 1 to 5 C a day. At 750-800 C crystal carrier is lifted and grown up crystals beyond the solution-melt are cooled to room temperature with velocity 40-50 C per 1 h. The thus prepared specimens for magnetoacoustic investigations have H = 1.8-2.0 e at frequency 9.1 Hz. EFFECT: improved procedure.