Einbau von Na2SO4 in die Hochtemperaturform des Na3PO4

Formation of Solid Solutions of Na₂SO₄ in the High-temperature Form of Na₃PO₄ The high-temperature form of Na₃PO₄ solves up to 70 mole-% Na₂SO₄ maintaining the type of crystal structure. The lattice constants increase from 742.3(1) pm (pure Na₃PO₄) to 749.1(2) pm for Na^3?x(PO₄)^?x(SO₄)_x (x = 0.7). The high-temperature form, in the case of pure Na₃PO₄ stable above 325°C, is stabilized at room-temperature by doping with small amounts of Na₂SO₄.