[NC4H12][(UO2)6(H2O)2(SO4)7] is the first organically templated actinide sulfate with a three-dimensional framework structure; it has channels of dimensions 8.5 A x 8.5 A, running along the [001] direction, containing tetramethylammonium cations.

Four organically templated uranyl phosphonates, [C4N2H12][UO2F(PO3CH3)]2 (UPNO-1), [C4N2H12][UO2(PO3CH3)(PO2(OH)CH3)]2 (UPNO-2), [C4N2H12][(U2O4F3)(UO2F(H2O))(PO3C6H5)2]·2H2O (UPNO-3), and [C4N2H12]2[(UO2)5(PO3CH2C6H5)6(PO2(OH)CH2C6H5)2] (UPNO-4) have been synthesized under hydrothermal conditions. UPNO-1 contains doubly protonated piperazine templates, [C4N2H12]2+, residing between [UO2F(PO3CH3)]1- anionic layers. Distinct hydrophobic and hydrophilic regions are present between [UO2(PO3CH3)(PO2(OH)CH3)]1- layers in UPNO-2. The template is found in the hydrophilic interlayer space only, completely segregated from the methyl groups of the uranyl methylphosphonate layer, which protrude into the hydrophobic interlayer space. UPNO-3 contains [(U2O4F3)(UO2F(H2O))(PO3C6H5)2]2- layers separated by both piperazine templates, [C4N2H12]2+, and phosphonate phenyl groups, which exist in the same interlayer region. In UPNO-4 the region between [(UO2)5(PO3CH2C6H5)6(PO2(OH)CH2C6H5)2]4- layers is completely hydrophobic as a result of the large number of benzyl groups occupying the interlayer space. The template is found in voids within each layer. The structures of these compounds are dependent upon the reactant concentrations. Crystal data for the compounds are as follows:  UPNO-1, a = 6.9288(3) Å, b = 8.1174(4) Å, c = 14.8505(9) Å, β = 91.7173(19)°, monoclinic P21/n (no. 14), Z = 2; for UPNO-2, a = 10.0682(4) Å, b = 8.9121(3) Å, c = 12.9631(7) Å, β = 90.4901(15)°, monoclinic P21/a (no. 14), Z = 2; for UPNO-3, a = 6.7796(1), b = 17.2821(4) Å, c = 24.6754(6) Å, orthorhombic Pbcm (no. 57), Z = 4; and for UPNO-4, a = 11.4732(2) Å, b = 14.9097(2) Å, c = 15.4480(3) Å, α = 64.2307(6)°, β = 70.2105(7)°, γ = 84.136(1)°, triclinic P1̄ (no. 2), Z = 2.

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The phase stability of organically templated uranium sulfates in the [UO(2)(CH(3)CO(2))(2).2H(2)O/homopiperazine/H(2)SO(4)] and [UO(2)(CH(3)CO(2))(2).2H(2)O/N,N-dimethylethylenediamine/H(2)SO(4)] systems has been studied using composition space. Two new compounds were formed in each system; [N(2)C(5)H(14)](2)[UO(2)(SO(4))(3)] (USO-17) and [N(2)C(5)H(14)][UO(2)(H(2)O)(SO(4))(2)] (USO-18) contain homopiperazine, and [N(2)C(4)H(14)][UO(2)(SO(4))(2)] (USO-19) and [N(2)C(4)H(14)][(UO(2))(2)(H(2)O)(SO(4))(3)].H(2)O (USO-20) contain N,N-dimethylethylenediamine. The relative stability of the products from each system is dependent upon the reactant mole fractions in the initial reaction gel. Crystal data: USO-17, a = 14.4975(3) A, b = 11.9109(3) A, c = 13.0157(3) A, beta = 110.475(1) degrees, monoclinic, C2/c (No. 15), Z = 4; for USO-18, a = 7.6955(2) A, b = 11.7717(3) A, c = 14.7038(4) A, orthorhombic, P22(1)2(1) (No. 18), Z = 4; for USO-19, a = 9.3322(1) A, b = 9.7743(2) A, c = 13.8897(3) A, orthorhombic, P2(1)2(1)2(1) (No. 19), Z = 4; and for USO-20, a = 11.2460(2) A, b = 10.5387(2) A, c = 17.0432(3) A, beta = 92.9884(6) degrees, monoclinic, P2(1)/c (No. 14), Z = 4.

The hydrothermal synthesis of uranium sulfates in the presence of a series of structurally related organic templating agents has been investigated. Piperazine, 2-methylpiperazine, and 1,4-diazabicyclo[2.2.2]octane, each of which is based upon the same six-membered cyclical diamine, exhibit different point symmetries and hydrogen-bonding characteristics. Small changes in the template structure result in marked differences in the reaction product. Three new compounds were synthesized and structurally characterized, [N2C4H12][UO2(H2O)(SO4)2], [N2C5H14][UO2(H2O)(SO4)2], and [N2C6H14][UO2(H2O)(SO4)2]. The inorganic framework of each compound was found to be dependent on the template structure. [N2C4H12][UO2(H2O)(SO4)2] consists of one-dimensional [UO2(H2O)(SO4)4/2]∞ 2- chains, which hydrogen bond to one another to form quasi two-dimensional layers. One-dimensional chains are observed in [N2C5H14][UO2(H2O)(SO4)2]. These chains, which have the formula [UO2(H2O)(SO4)4/2(UO2(H2O)(SO4)2)]∞ 4- are unprecedented in uranium chemistry. Two-dimensional layers are observed in [N2C4H12][UO2(H2O)(SO4)2]. Each uranyl [UO2]2+ unit is bound to one water molecule and four bridging sulfate tetrahedra.