Single crystals of RVO4 (R = Y,Gd) doped with optically active element like Nd have been obtained under mild hydrothermal conditions (T = 240 degrees C P similar to 80 bars). A detailed mechanism of the crystallization process, which helps in the considerable reduction of the PT conditions of the growth of these high-melting (m.p. > 1800 degrees C) crystals has been formulated. The crystals obtained have been subjected to morphological, X-ray powder diffraction and infrared spectroscopic studies. (c) 2007 Elsevier B.V. All rights reserved.