Phase-transition variation with composition in solid solutions of K₂Cd₂(SO₄)₃ with Tl₂Cd₂(SO₄)₃

Polycrystalline samples of (K_xTl_{1 − x})₂Cd₂(SO₄)₃ have been prepared with x = 0[0.125]1.0. The phase transition temperature, liquidus and solidus temperatures, lattice parameters and unit-cell volume at 298 K have been determined for each composition. The phase transition temperature varies linearly with x for 0.125 ≤ x ≤ 1.0, and the solidus curve varies linearly with x over the entire range. Mixed crystals are cubic at 298 K for x ≤ 0.645 and are orthorhombic at higher values of x. The cubic lattice parameter varies linearly with x for 0.125 ≤ x ≤ 0.645, the lengths of the orthorhombic a, b and c axes vary linearly with xfor 0.645≤x ≤ 1.0, and the unit-cell volume varies linearly with x for 0.125≤ x≤ 1.0.