Crystal Structures of the Newly Synthesized Kdy and Ktb Aluminosilicates

Abstract

The crystal structures are determined for KDy[AlSi₄O₁₂]·0.41H₂O and KTb[AlSi₄O₁₂]·0.32 H₂O compounds synthesized under hydrothermal conditions, which crystallize in the space group C2/c with the unit cell parameters a = 26.6956(6) Å and 26.619(1) Å, b = 7.2477(2) Å and 7.2553(3) Å, c = 14.7705 Å and 14.8200(6) Å, β = 123.7721° and 123.5149° for KDy and KTb aluminosilicates respectively. Tetrahedral layers in the structures of the studied crystals differ in their packing order and can be matched in space with a twofold rotational symmetry axis. In the studied phases Dy and Tb present in a trivalent form.