Structural diversity in organically templated uranium sulfates

The potential of organic amine templates to direct the synthesis of metal sulfate frameworks has been investigated. Eight novel uranyl sulfates have been prepared using a templated uranyl sulfate precursor under hydrothermal conditions. The topologis of the isolated phases vary from the molecular (0-D), to chains (1-D) to layered (2-D) frameworks. [N4C6H22]2[(UO2)2(SO4)6](USO-10) is molecular or zero-dimensional. Two different types of one-dimensional uranyl-containing chains have been observed. [N2C4H12][UO2(H2O)(SO4)2](USO-3), [N2C5H14][UO2(H2O)(SO4)2](USO-4) and [N2C3H12][UO2(H2O)(SO4)2](USO-9) contain chains based upon a [UO2(SO4)4/2] backbone. [N2C10H10][UO2(SO4)2]·H2O (USO-6) and [N2C6H18][(UO2)2(H2O)3(SO4)3](USO-7) contain chains based upon a [UO2(SO4)3/3] backbone. Two layered or two-dimensional compounds, [N2C6H14] [UO2(H2O)(SO4)2](USO-5) and [N2C3H5]2[(UO2)2(SO4)3](USO-8) have also been isolated. All the new phases have been characterised using a range of physical techniques including single crystal X-ray structure analysis.