G. V. Zimina

Synthesis of complex cesium hydrosulfatophosphates

Solubility of the CsH2PO4-CsHSO4-H2O system has been studied using the isothermal method (25.0°C); the compounds Cs4(HSO4)3(H2PO4), Cs3(HSO4)2(H2PO4), and Cs5(HSO4)2(H2PO4)3 have been found to form; Cs5(HSO4)2(H2PO4)3 has been obtained for the first time. Single crystals of the isolated phases have been grown. Their composition has been determined, and agreement between the results of studying solid phases in the CsH2PO4-CsHSO4-H2O and these single-crystal samples has been demonstrated. X-ray diffraction analysis of these phases has been carried out.

Phase formation in the ScPO4-Na3PO4-Li3PO4 ternary system

The 950°C isothermal section of the InPO4-Na3PO4-Li3PO4 ternary system was studied and constructed; one-, two, and three-phase fields are outlined. Five solid-solution regions exist in the system: solid solutions based on the complex phosphate LiNa5(PO4)2 (olympite structure), the indium ion stabilized high-temperature Na3PO4 phase (Na3(1 − x)Inx(PO4); space group Fm

How synthesis parameters influence the quality of lead magnesioniobate PbMg1/3Nb2/3O3

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Phase Stability and Ionic Conductivity of Solid Solutions with NASICON Structure

m), the complex phosphate Na3In2(PO4)3, and the α and β phases of the compound Li3In2(PO4)3. A narrow region of melt was found in the vicinity of eutectic equilibria. All the phases detected in the system are derivatives of phases existing in the binary subsystems. Isovalent substitution of lithium for sodium in Na3In2(PO4)3 leads to a significant increase in the region of a NASICON-like solid solution.

Phase formation in ScPO4–Na3PO4–Li3PO4 ternary system

Lead magnesioniobate PbMg1/3Nb2/3O3 (PMN) has been prepared using lead oxide and magnesium niobate. Factors that influence the perovskite/pyrochlore ratio in the PMN structure have been studied. In order for the maximal amount of the perovskite phase to be obtained, synthesis should be carried out at 850–900°C; an excess of MgO (1–5 wt %) does not exert a positive effect. An excess of PbO (5–7 wt %) allows one to obtain a phase that contains 85% PMN, with the perovskite structure. The perovskite lattice is found to be stabilized as a result of cationic substitutions (Yb, Lu) in the Mg-Nb sublattice due to the formation of solid solution Pb(Mg1/3Nb2/3)1 − xYb(Lu)xO3, where 0 ≤ x ≤ 0.9.