The Double Phosphates M I M II PO4 (M I : Na, K; M II : Mg, Mn, Co, Ni, Zn) -Synthesis from Chloride Melts and Characterization. -Interactions in the systems M I PO3-M II O (or Mn2O3)-M I Cl (M I : Na, K; M II : Mg, Co, Ni, Zn) are investigated at molar ratios P/M x = 1 or 2, and M I Cl/(M I PO3 + M II O) = 30 (porcelain crucibles, 1073 K, 3-5 h). The samples are characterized by powder XRD, FTIR spectroscopy, and UV/VIS diffuse reflectance spectroscopy. The main advantages of the synthesis of the title compounds from chloride melts are synthesis time reduction, reduced reaction temperature, and the possibility of crystal size control. -(LIVITSKA*, O. V.; STRUTYNSKA, N. Y.; ZATOVSKY, I. V.; SLOBODYANIK, N. S.; Cryst. Res. Technol. 50 (2015) 8, 626-632, http://dx.