Les systèmes MFTlF3 (M = Li,Na, K)

A large number of new phases have been prepared and characterized in the MFTlF₃ system: Na₃TlF₆ isostructural with cryolite, Na₃Tl₂F₉, Na_xTl_1−xF_3−2x (0.425 ? x ? 0.565 at 500°C) and Na₅Tl₉F₃₂ related to the fluorite type, K₃TlF₆ with a structure similar to that of (NH₄)₃FeF₆, K₅Tl₃F₁₄ with the chiolite structure, Na_yTl_1−yF_3−2y (0.12 ? y ? 0.14 at 500°C) and K₂Tl₇F₂₃ affiliated to α-UO₃, KTlF₄, and KTl₂F₇.