Amine-Templated Linear Vanadium Sulfates with Different Chain Structures

Amine-templated vanadium sulfates of the formula [HN(CH2)6NH][(VlvO)2(OH)2(SO4)2]-H2O, 1, [H3N(CH2)2NH3][Vlll(OH)(S04)2]-H20, II, and [h2n(CH2)4NH2][VlvO)(h2o)(so4)2], III, have been prepared under hydrothermal conditions. These vanadium sulfates add to the new emerging family of organically templated metal sulfates. Compound I has a linear chain structure consisting of V2O8 square-pyramid dimers connected by corner-sharing SO4 tetrahedra, creating four-membered rings along the chain. Both II and III possess simple linear chain topologies formed by VO6 octahedra and SO4 tetrahedra, with II having the tancoite chain structure. Compound I crystallizes in the triclinic space group PI (No. 2) with a = 7.4852(4) A, b = 9.5373(5) A, c = 11.9177(6) A, alpha = 77.22°, beta = 76.47(2)°, gamma = 80.86°, Z = 2. Compound II: monoclinic, space group P21/c (No. 14), a = 6.942(2) A, b = 10.317(3) A, c = 15.102(6) A, beta = 90.64(4)°, Z= 4. Compound III: triclinic, space group PI (No. 2) with a = 6.2558(10) A, b = 7.0663(14) A, c = 15.592(4) A, a = 90.46(2)°, beta = 90.47(2)°, gamma - 115.68(2)°, Z = 2. Magnetic susceptibility measurements reveal weak antiferromagnetic interactions in I and III and ferromagnetic interactions in II.