CRYSTAL-CHEMICAL AND DIELECTRIC INVESTIGATION OF THE SYSTEM LIZNV1-XPXO4

An X-ray crystallographic study has allowed us to identify a solid sol ution of the type LiZnV1-xPxO4 (0 less than or equal to x less than or equal to 10.6) inside the binary system LiZnVO4-LiZnPO4. The structur e is isotypic with the phenacite like LiZnVO4. X-ray diffraction patte rns are indexed according to the lattice parameters of the trigonal sy stem and the space group R3. The mother structure can be regarded as m ade of a three-dimensional network of LiO4, ZnO4 and VO4 tetrahedra al l having one apex oriented along [001]. The peaks, observed on the cur ves of the thermal variation of the dielectric constants, have allowed us to recognize a phase transition whose temperature varies continuou sly along the solid solution.