Abstract
The perfection of crystals of TbVO 4 and TmVO 4, which were grown from Pb 2V 2O 7 flux by slow cooling and recovered by using a hot pouring technique, has been studied by X-ray anomalous transmission topography. The dislocation density was found to be very low (Čáslavsky 10 2 cm -2) except in the regions immediately behind the termination facets. Most of the contrast in the topographs was due to precipitates and a strained layer or “skin” at the surface of the crystals, and this contrast was appreciably changed by annealing at a high temperature. Evidence of plastic deformation was found in some crystals, but dislocations due to gross flux inclusions extended only for short distances and nearly perfect material was found between inclusions. The perfection of solid solutions of (Tm, Lu)VO 4 and (Tb, Gd)VO 4 was found to be comparable with that of TmVO 4 and TbVO 4.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
