Amine-templated one-dimensional metal sulfates including a mixed-valent Fe compound with a half-kagome structure

Organically templated metal sulfates are relatively new. Six amine-templated transition-metal sulfates with different types of chain structures, including a novel iron sulfate with a chain structure corresponding to one half of the kagome structure, were synthesized by hydro/solvothermal methods. Amongst the one-dimensional metal sulfates, [C10N2H10][Zn(SO4)Cl-2] (1) is the simplest, being formed by corner-linked ZnO2Cl2 and SO4 tetrahedra. [C6N2H18][Mn(SO4)(2)(H2O)(2)] (2) and [C2N2H10][Ni(SO4)(2)(H2O)(2)] (3) have ladder structures comprising four-membered rings formed by SO4 tetrahedra and metal-oxygen octahedra, just as in the mineral krohnkite. [C4N2H12][V-III(OH)(SO4)(2)]center dot H2O (4) and [C4N2H12][VF3(SO4)] (5) exhibit chain topologies of the minerals tancoite and butlerite, respectively. The structure of [C4N2H12][H3O][(FeFeF6)-Fe-III-F-II(SO4)] (6) is noteworthy in that it corresponds to half of the hexagonal kagome structure. It exhibits ferrimagnetic properties at low temperatures and the absence of frustration, unlike the mixed-valent iron sulfate with the full kagome structure.