Synthese und Struktur saurer Ubergangsmetallsulfate - Ti(H₅O₂)(SO₄)₂(H₂O)₂ und Zr(H₃O)₂(SO₄)₃ / Synthesis and Structure of Acid Transition Metal Sulfates - Ti(H₅O₂)(SO₄)₂(H₂O)₂ und Zr(H₃O)₂(SO₄)₃

Abstract

Abstract From the ternary system M n (SO 4 ) n/2 / SO 3 / H 2 O (M n+ = Zr 4+ , Ti 3+ ) two new acid metal sulfates, Ti(H 5 O 2 )(SO 4 ) 2 (H 2 O) 2 and Zr(H 3 O) 2(SO 4 ) 3 , have been synthesized and structurally characterized. Ti(H 5 O 2 )(SO 4 ) 2 (H 2 O) 2 crystallizes in the orthorhombic space group Pnma with cell parameters a = 9.858(5), b = 18.32(2), c = 5.437(7)Å (Z = 4); Zr(H 3 O) 2 (SO 4 ) 3 crystallizes in the triclinic space group P1 with cell parameters a = 5.092(2), b = 8.533(3), c = 12.388(6)A, α = 92.95(3)°, β = 90.89(3)°, γ = 94.35(3)° (Z= 2). In the titanium compound there are slightly distorted TiO 6 octahedra with Ti-O distances between 1.99 and 2.09 Å which are sharing corners with SO 4 tetrahedra. Through hydrogen bonds layers are formed perpendicular to the b-axis. These layers are connected by H 3 O + ions only. The structure of Zr(H 3 O) 2 (SO 4 ) 3 consists of three different SO 4 tetrahedra and distorted ZrO 7 polyhedra which are connected via common corners and edges to form columns parallel to the a-axis. The Zr-O distances vary from 2.13 to 2.18Å for equatorial positions, significantly longer than the axial Zr-O distances with 2.05Å.