A new layered magnesium zinc phosphate hydrate, MgZn(HPO4)(2)center dot H2O, with a zinc phosphate framework isostructural with the one of Na2Zn(HPO4)(2)center dot 4H(2)O, was prepared by the direct ambient pressure and temperature reaction between zinc 2,4-pentanedionate, phosphoric acid and hexahydrated magnesium chloride. The as-prepared sample is monoclinic (a = 8.780(7) angstrom, b = 13.240(7) angstrom, c = 11.123(0) angstrom and beta = 116.21(2)degrees). The prepared solid undergoes two thermal transformations when it is heated from 110 to 600 degrees C. The first transformation is due to the release of intercalated water molecules and the second one is due to the HPO42- --< P2O74- transition. (C) 2006 Elsevier Ltd. All rights reserved.