Hydrothermal synthesis of the first organically templated open-framework uranium phosphate

[(C2H5)2NH2]2[(UO2)5(PO4)4] was prepared from U3O8, HONEt2 and phosphoric acid under hydrothermal conditions (180 degrees C, 5 days) and represents the first three-dimensional open-framework uranium phosphate prepared to date.     

Synthesis, structure, and upconversion studies on organically templated uranium phosphites

Three new amine templated uranium phosphites, [C2N2H10][U2IVF6(HPO3)2], 1, [C4N2H12][U2IVF6(HPO3)2], 2, and [C4N2H12][(UVIO2)2F2(HPO3)2], 3, have been synthesized by hydrothermal methods. All of the compounds are built up from a connectivity between U(O/F)x (x = 7, 8) and HPO3 polyhedral units. The observation of a well-established secondary building unit, SBU-4, in 1 and 2 is noteworthy. In 1, the SBU-4 units are connected to form U-F-U chains, which are linked by U-O-P chains, forming the layered structure. In 2, the SBU-4 units are edge-shared and also interconnected forming the 3D structure. In 3, the connectivity between the building units forms a layer, the topology of which is similar to the mineral, johannite. To the best of our knowledge, this is the first observation of a well-known secondary building unit (SBU-4) in actinide framework compounds. Optical studies on 1 and 2, containing U(4+) species, indicate an intense blue emission through an upconversion process, and the magnetic susceptibility studies show antiferromagnetic behavior.     

An organically templated Co(II) sulfate with the kagome lattice

An amine-templated cobalt(II) sulfate with the kagome lattice, prepared for the first time, exhibits magnetic properties comparable to those of the analogous Fe(III) compounds.     

An organically templated iron sulfate with a distorted Kagome lattice exhibiting unusual magnetic properties

A layered iron sulfate of the composition [H3N(CH2)2NH2(CH2)2NH2(CH2)2NH3][FeII3F6(SO4)2], possessing a distorted Kagome lattice, prepared hydrothermally, is found to exhibit magnetic hysteresis like a ferrimagnet besides the characteristics of a frustrated system, like those of a spin glass.     

An organically templated open-framework cobalt germanate

An open-framework cobalt germanate of the formula, [Co₂(NH₂(CH₂)₂NH₂)₃][Ge₉O₁₈(OH)₄] has been prepared under solvo/hydrothermal conditions in the presence of ethylenediamine. The germanate is constructed by Ge₉O₁₈ clusters and contains eight- and ten-membered channels. Besides connecting two Co sites, the amine also acts as a bis-chelating agent and protrudes into the eight-membered channel.     

A new organically templated magnesium sulfate: structure, spectroscopic analysis, and thermal behaviour

A new magnesium sulfate templated by 2-methylpiperazine, (C₅H₁₄N₂)[Mg(H₂O)₆](SO₄)₂, was prepared by the slow evaporation method. The obtained crystals were investigated by the Raman and FTIR spectroscopy and crystallographically characterised by single-crystal X-ray diffraction. The compound crystallises in the monoclinic system, space group P2₁/n. Supramolecular network of this hybrid material consists of Mg²⁺ cations octahedrally coordinated by six water molecules, sulfate tetrahedra and protonated and disordered diamine linked together by two types of hydrogen bonds: OW—H…O and N—H…O. Dehydration of the title compound takes place in three steps. Thermal decomposition of the anhydrous phase consists in the loss of the organic moiety and one sulfate group leading to the formation of magnesium sulfate.     

The first organically templated linear metal selenate

An organically templated cadmium selenate of the formula [enH₂][Cd(H₂O)₂(SeO₄)₂], , has been synthesized by carrying out the reaction between CdO and H₂SeO₄ in the presence of the amine in aqueous medium at 80°C. The structure of involves isolated infinite [Cd(H₂O)₂(SeO₄)₂]²⁻ chains running along the c-axis, with the protonated ethylenediamine molecules between them. Crystal data for are as follows: Monoclinic, space group=C2/c, a=10.5059(7), b=10.3605(7), , β=94.666(2)°, , z=8, R₁=0.0237, wR₂=0.0500 (for all data).     

New organically templated photoluminescence iodocuprates(I)

Two types of organic cyclic aliphatic diamine molecules piperazine (pip) and 1,3-bis(4-piperidyl)propane (bpp) were used, respectively, to react with an inorganic mixture of CuI and KI in the acidic CH₃OH solutions under the solvothermal conditions, generating finally three new organically templated iodocuprates as 2-D layered [(Hpip)Cu₃I₄] 1, 1-D chained [tmpip][Cu₂I₄] 2 (tmpip=N,N,N′,N′-tetramethylpiperazinium) and dinuclear [H₂bpp]₂[Cu₂I₅] I·2H₂O 3. Note that the templating agent tmpip²⁺ in compound 2 originated from the in situ N-alkylation reaction between the pip molecule and the methanol solvent. The photoluminescence analysis indicates that the title compounds emit the different lights: yellow for 1, blue for 2 and yellow-green for 3, respectively.     

Controlled structural variations in templated uranium sulfates

A series of experiments in the UO(2)(CH(3)CO(2))(2).2H(2)O/H(2)SO(4)/1-(2-aminoethyl)piperazine/H(2)O system were conducted to determine the effects of variation in initial reactant concentrations on the reaction products. Several reaction gels were produced, in which the composition varied from 16:80:4:500 UO(2)(CH(3)CO(2))(2).2H(2)O/H(2)SO(4)/1-(2-aminoethyl)piperazine/H(2)O to 4:92:4:500 UO(2)(CH(3)CO(2))(2).2H(2)O/H(2)SO(4)/1-(2-aminoethyl)piperazine/H(2)O. Single crystals of two new organically templated uranium sulfates, [N(3)C(6)H(18)](2)[(UO(2))(5)(H(2)O)(SO(4))(8)].5H(2)O and [N(3)C(6)H(18)][(UO(2))(2)(H(2)O)(SO(4))(3)(HSO(4))].4.5H(2)O, were isolated. Both compounds exhibit structures in which the inorganic frameworks are two-dimensional and the protonated amines reside between layers, participating in extensive hydrogen bonding. The composition and structure of each compound is dependent on the nature of the starting concentrations. Crystal data: for [N(3)C(6)H(18)](2)[(UO(2))(5)(H(2)O)(SO(4))(8)].5H(2)O, monoclinic, space group P2(1)/n (No. 14), a = 21.5597(3) A, b = 10.2901(2) A, c = 22.8403(3) A, beta = 96.7436(7) degrees, and Z = 4; for [N(3)C(6)H(18)][(UO(2))(2)(H(2)O)(SO(4))(3)(HSO(4))].4.5H(2)O, monoclinic, space group P2(1)/a (No. 14), a = 15.7673(4) A, b = 10.5813(3) A, c = 16.7710(5) A, beta = 99.9216(9) degrees, and Z = 4.     

Syntheses, characterizations and crystal structures of three new organically templated or organically bonded zinc selenates

Three new organically templated or organically bonded zinc selenates, namely, {H₂bipy}Zn(SeO₄)₂(H₂O)₂1 (bipy=4,4′-bipyridine), {H₂pip}{Zn(SeO₄)₂(H₂O)₄}·2H₂O 2 (pip=piprazine), and Zn(SeO₄)(phen)(H₂O)₂3 (phen=1,10-phenanthroline) have been synthesized by hydrothermal reactions. The structure of compound 1 features a 1D chain composed of [Zn(SeO₄)₂(H₂O)₂]²⁻ anions. Compound 2 has a 2D layer structure built from {Zn(SeO₄)₂(H₂O)₄}²⁻ anions that are cross-linked by doubly protonated piperazine cations via N-H?O hydrogen bonds. The structure of compound 3 contains a 1D chain of Zn(SeO₄)(phen)(H₂O)₂, such chains are further interlinked by hydrogen bonds and π?π interactions to form a 〈200〉 layer. The different roles the templates played have also been discussed.     

Exploration of composition space in templated uranium sulfates

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.     

Syntheses and crystal structures of two new organically templated borates

Two new organically templated borates, [H₃N(C₆H₁₀)NH₃][B₄O₅(OH)₄] (1) and [H₃N(C₆H₁₀)NH₃][B₅O₈(OH)] (2) have been synthesized in the presence of trans-1,4-diaminocyclohexane acting as a structure-directing agent under mild solvothermal conditions. The structures were determined by single crystal X-ray diffraction and further characterized by FTIR, elemental analysis and thermogravimetric analysis. Compound 1 crystallizes in the monoclinic system, space group C2/c (No. 15), , , , β=105.258(6)°, , Z=4. The structure contains supramolecular hydrogen-bonded network formed by isolated [B₄O₅(OH)₄]²⁻ polyanions. 2 is monoclinic, space group P2(1)/n (No. 14), , , , β=91.897(6)°, , Z=4. The structure consists of layers of 3,9-membered boron rings constructed from pentaborate anion groups [B₅O₈(OH)]²⁻. The adjacent borate layers are further linked with each other by hydrogen bond to form a 3D supramolecular network. It is the first example of layered borates templated by an organic amine.     

The first organically templated open-framework metal selenate with a three-dimensional architecture

A three-dimensional metal selenate of the formula [C2N2H10][La2(SeO4)4(H2O)3].H2O, comprising La2Se4 building units and possessing 12-membered channels, has been prepared in an acidic medium under hydrothermal conditions.     

Syntheses and crystal structures of the first organically templated metal tellurites

The first organically templated vanadium tellurites, [H₂en][(VO₂)(TeO₃)]₂·H₂O (1, en=ethylenediamine) and [H₂pip][(VO₂)(TeO₃)]₂ (2, pip=piperazine) have been synthesized by hydrothermal reactions and structurally characterized. Both compounds feature a [(VO₂)(TeO₃)]⁻ anionic layer containing V₂Te₂ four-member rings and V₄Te₄ eight member rings. The vanadium (V) atom is five coordinated by three tellurite oxygens and two terminal oxygen atoms in a distorted trigonal bipyramidal geometry. The interconnection of the VO₅ polyhedra by bridging tellurite groups leads to a 2D corrugated anionic inorganic layer. The doubly protonated template cations and the lattice water molecules in 1 are located at the interlayer space and are involved in hydrogen bonding. The doubly protonated template cation in 2 is not involved in hydrogen bonding with the anionic inorganic layer.     

An organically templated yttrium fluoride with a ‘Super-Diamond’ structure

An organically templated yttrium fluoride has been prepared hydrothermally and characterised by X-ray powder diffraction. The crystal structure of [C₃N₂H₁₂]_0.5[Y₃F₁₀] may be regarded as a ‘Super-Diamond’ framework, space group Fd, a=15.4817(1) Å, where each carbon atom site of the diamond structure is replaced by a polyhedral [Y₆F₈F_24/2]²⁻ unit. The basic framework type is isostructural with the known phase (H₃O)[Yb₃F₁₀]·H₂O. The novelty in the present case lies in the use of the organic structure-directing agent 1,3-diaminopropane.     

Crystal architecture and thermal decomposition of two new organically templated cadmium sulfates

Two organic-inorganic hybrid compounds (C₅H₁₄N₂)[Cd(H₂O)₆](SO₄)₂ (I) and R-(C₅H₁₄N₂)×[Cd(H₂O)₆](SO₄)₂ (II) are synthesized by the slow evaporation method and characterized by single crystal X-ray diffraction, thermogravimetry, temperature-dependent X-ray diffraction, and infrared spectroscopy. The first compound crystallizes in the centrosymmetric space group P2₁/n with the following unit cell parameters: a = 6.6208(2) Å, b = 10.6963(3) Å, c = 12.9318(4) Å, V = 893.05(6) ų, and Z = 2. Its structure is solved by direct methods and refined by the least-squares analysis [R ₁ = 0.0389 and wR ₂ = 0.0821]. This compound shows a crystallographic disorder II destroys the inversion symmetry and leads to a fully ordered structure. Indeed, compound II crystallizes in the non-centrosymmetric space group P2₁ with the following unit cell parameters: a = 6.6306(1) Å, b = 10.7059(2) Å, c = 12.9186(1) Å, V = 894.67(2) ų, and Z = 2. The crystal structure of both compounds is built from isolated SO ₄ ^2? anions, disordered 2-methylpiperazinediium, (C₅H₁₄N₂)²⁺ in compound I or R-2-methylpiperazinediium R-(C₅H₁₄N₂)²⁺ in compound II, and divalent metal cations surrounded by six water molecules. These different entities are connected together only by a 3D hydrogen bond network. The thermodiffractometry and the thermogravimetric analyses indicate that the decomposition of the supramolecular precursors proceeds through several stages leading to cadmuim oxide.     

Hydrothermal synthesis and characterization of two organically templated cadmium borophosphates with novel structures

Two organically templated cadmium borophosphates, (C(4)H(16)N(3))[CdClB(2)P(3)O(12)(OH)] (1) and (C(2)H(10)N(2))[CdB(2)P(3)O(12)(OH)] (2), were synthesized hydrothermally in the presence of structure-directing amines. Compound 1 has a complex layered structure (orthorhombic, Pbca (No. 61); a = 9.470(2), b = 12.307(3), c = 27.311(6) A; V = 3183 (1) A(3); Z = 8) with a 9MR channel system, while compound 2 (orthorhombic, Pbca (No. 61); a = 9.286(3), b = 12.459(3), c = 21.626(6) A; V = 2502(1) A(3); Z = 8) presents a 3-dimensional open framework structure of different types of intersecting channels. It is worth noting that both the Cl(-) anions and the organic templates play important and interesting roles in the formation of the structures.