Improved flux growth of rare earth arsenates RAsO4

The tetragonal rare-earth arsenates (R = Lu to Sm) have previously been grown as small crystals from Pb2As2O7 as flux. Attempts to prepare larger crystals by modifying the flux and controlling evaporation by means of a crystalline seal are described. The crystal size was increased by 1 to 2 orders of magnitude. The preparation of the monoclinic arsenates (R = Nd to La) is also described.