Influence of fluorides on phase relations in the molten systems MI2O-Р2О5 Mn2O3/MIIO, МI – Li, Na, K; MII – Ni, Co


  • Olga Petrenko Taras Shevchenko National University of Kyiv
  • Ruslan Lavrik National University of Life and Environmental Sciences of Ukraine
  • Kateryna Terebilenko Taras Shevchenko National University of Kyiv
  • Volodymir Trachevsky G.M.Kurdyumov Institute for Metal Physics of the N.A.S. of Ukraine
  • Valentyna Galimova National University of Life and Environmental Sciences of Ukraine



double phosphates, solubility curves, phosphate, fluoride, flux synthesis


Addition of alkaline fluorides to molten phosphates with a composition MI2O-Р2О5-Mn2O3 and MI2O-Р2О5-MIIO (МI – Li, Na, K) gradually changes the solubility of polyvalent metals oxides and shifts the crystallization areas in the corresponding melts. The results obtained are based on solubility curves found for Mn2O3, СоО and NiO in the fluxes of MI2O-Р2О5 -MF and MI2O-Р2О5 -MF (where МI – Li, Na, K) and X-Ray diffraction, IR spectroscopy and thermal analysis. The presence of 10 and 20 % mass of fluorides provides molten polyphosphates depolymerization and yields pyro- Li2MnP2O7, K2CoP2O7, Na2CoP2O7and orthophosphates Na2Mn3(P2O7)2, NaMnPO4, NaNiPO4 single crystals growth.


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