Microcrystals of Th1/4Zr2(PO4)(3) were synthesized by thermal treatment (900 degrees C) of the material obtained using sol-gel technology (including organic complex formation and etherification), Their structure [hexagonal, P (3) over barc, a = b = 8.7311(4) angstrom, c = 23.309(2) angstrom] includes the three-dimensional [Zr-2(PO4)(3)](-) NASICON-type network and extraframework 6-fold-coordinated thorium(IV) cations.