INVESTIGATIONS OF ALKALINE RARE-EARTH ORTHOPHOSPHATES M3RE(PO4)(2)

A preparation route to synthesize rubidium and/or potassium rare earth double phosphate powders of the type M3RE(PO4)(2) (RE=La, Ce, Eu, Gd, Tb) as pure phases in a solid state reaction is described. The essent ial fact of the reaction is to make use of the low particle size of fr eshly precipitated rare earth phosphate REPO4.nH(2)O as a starting mat erial. Properties of the materials are described. (C) 1998 Elsevier Sc ience S.A.