Anionic Chain Structure Research Articles

Giant Anisotropic Thermal Expansion Phase Transition of Silver Iodide Anionic Organic-Inorganic Hybrid.

Hybrid metal halide materials with charming phase transition behaviors have attracted considerable attention. In former works, much attention has been focused on the phase transition triggered by the order-disorder or displacement motions of the organic component. However, manipulating the variation of the inorganic component to achieve the phase transition has rarely been reported. Herein, two novel organic-inorganic hybrid materials, [THPM]n[AgX2]n (THPM = 3,4,5,6-tetrahydropyrimidin-1-ium, X = I for 1 and Br for 2) with the [AgX2]nn- anionic chain structure, were synthesized. At 293 K, the [AgX2]nn- chains in 1 were constructed by the tetramer units of Ag atoms, while that in 2 was assembled by the dimer structure. Upon heating to 355 K, owing to the variation of the metallophilic interaction between adjacent Ag atoms, a unique transformation process from tetramer to dimer in [AgI2]nn- chains of 1 can be detected and endow 1 with a giant anisotropic thermal expansion with linear strain of ∼7% and shear strain of ∼20%, which can be used as a mechanical actuator for switching. Alternatively, for 2, no phase transition process can be observed upon the temperature variation. This work provides an effective approach to design phase transition materials triggered by the inorganic part.

Hybrid Supramolecules for Azolium-Linked Cyclophane Immobilization and Conformation Study: Synthesis, Characterization, and Photocatalytic Degradation.

In this paper, one imidazole macrocyclic divalent cation with a flexible configuration was chosen with the aim of the immobilization of its conformation. Six novel organic–inorganic hybrid supramolecules {([syn/anti-did](CdI4)(C2H3N)} (1), {([syn/anti-did](HgI4)(C2H3N)} (2), {([syn/syn-did](Pb2I8)(PbI5)} (3), {([syn/syn-did](Bi2I8)(BiI5)} (4), {([syn/syn-did](Ag4Br6)}n (5), and {([syn/anti-did](Ag2I4)} (6) [did2+ = (12z, 52z)-11H, 51H-1, 5(1, 3)-diimidazol-3-iuma-3, 7(1, 2)-dibenzenacyclooctaphane-13, 53-diium] have been synthesized through the self-assembly reaction of did2+ with different metals under solvothermal reaction. These compounds have been unambiguously confirmed by powder X-ray diffraction, IR, thermogravimetric and X-ray single-crystal diffraction. Crystallographic analysis shows that the anions of compounds 1 and 2 are isostructural with mononuclear anion structure, the anions of compounds 3, 4, and 6 are of binuclear structure, and compound 5 anion is a one-dimensional anionic chain structure. Imidazole cyclophanes of organic cations may exist in a syn/syn-conformation in 3–5 or syn/anti conformation in 1, 2, 6, but tilting angles in compounds 1–6 were different. This article described the photocatalytic degradation of organic dye in waste water and the optical band gap of compounds 1–6. The calculated semiconductor band gap of compounds 1–6 is smaller than that of TiO2, so compounds 1–6 have semiconductor properties. Compound 1 has the smallest band gap value, and the photocatalytic performance is the best.

Structural systematic design of organic templated samarium sulfates and their luminescence property

Four organic amine templated samarium sulfates[(CH3)2NH2]9[Sm5(SO4)12] 1, [NH3(CH2)2NH3]4[Sm2(SO4)7] 2, [H3O]2[(CH3)2NH2][Sm(SO4)3] 3 and [(CH3)2NH2]3[Sm(SO4)3] 4 have been solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Compound 1 exhibits a 3D porous structure containing intersecting extra-large 20-membered ring channels; compound 2 is a 2D corrugated layered sulfate constructed by two different zigzag chains and 12-membered rings; compound 3 exhibits a 1D anionic chain structure compensated by protonated dimethylamine and water cations occluded in the helical [Sm–O–S]n chains, and compound 4 is a novel 1D sulfate constructed by tetrameric [Sm2(SO4)2O10] unit and 4-membered rings. The syntheses of compounds 3 and 4 demonstrate that large organic amine (1,3,5-triazine-2,4,6-triamine or 4,4′-diaminobiphenyl) may be used as second structural directing agent (SDA) to prevent the formation of high dimensional inorganic framework as well as induce crystal growth of 1D chain structural samarium sulfate. The luminescent properties of compounds 1–4 were investigated. The strong luminescence of 3 in the orange light (598 nm 4G5/2→6H7/2) region indicates it is an excellent candidate for orange fluorescent materials.

Solvothermal synthesis, crystal structure and properties of three new 1D and 3D organically templated lanthanide sulfates

Three new organic amine templated lanthanide sulfates [(CH3)2NH2]3[Y(SO4)3]·H2O 1 and [(CH3)2NH2]9[Ln5(SO4)12]·2H2O (Ln=La 2 and Ce 3) have been solvothermally synthesized under similar conditions and structurally characterized by single-crystal X-ray diffraction. Compound 1 exhibits 1D anionic chain structure compensated by protonated dimethylamine occluded in the helical [Y–O–S]n chains, while the 3D inorganic frameworks of 2 and 3 contain extra-large 20-membered ring channels. The syntheses of three compounds demonstrates that although yttrium and lanthanide belong to one family, the self-assembly of yttrium sulfate may be different from other rare-earth sulfates because Y is much lighter. The formation of 1–3 also demonstrates that the solvent plays an important role during the synthesis.

Second structural directing agent induces the formation of 1D organic templated terbium sulfate

Two organic amine templated 1D terbium sulfates(H3O)2(C2H8N)[Tb(SO4)3] 1 and 3D (C2H8N)9[Tb5(SO4)12]·2H2O 2 have been solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Compound 1 exhibits a 1D anionic chain structure compensated by protonated dimethylamine and water cations occluded in the helical [Tb–O–S]n chains, while the 3D inorganic framework of 2 contains extra-large 20-membered ring channels. The synthesis of both compounds demonstrates that a large organic amine (1,3,5-triazine-2,4,6-triamine) may be used as the second structural directing agent (SDA) to prevent the formation of a high dimensional inorganic framework as well as inducing crystal growth of 1D structural terbium sulfate chain of 1. Because of the excellent luminescent properties of Tb3+, compounds 1 and 2 were investigated. The very strong luminescence in the green light region indicates 1D compound 1 is an excellent candidate for green fluorescent materials.

ChemInform Abstract: (1,4‐dabH)2MnSnS4: The First Thiostannate with Integrated Mn2+ Ions in an Anionic Chain Structure.

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Catena-Poly[tetramethylammonium [argentate(I)-di-μ-bromido

The title compound, {(C4H12N)[AgBr2]}n, is isomorphous with its chloride analogue [Helgesson, Josefsson & Jagner (1988). Acta Cryst. C44, 1729–1731]. It displays a one-dimensional ∞1[Ag2Br4]n2n− anionic chain structure accompanied by isolated tetra­methyl­ammonium cations. All the crystallographically independent non-H atoms lie on special positions, namely Ag on 2mm, Br on mm2 or m2m, N on mm2, and C on sites of symmetry ma or mb. The tetra­methyl­ammonium cations reside between these anionic chains, with weak C—H⋯Br hydrogen-bonding inter­actions forming a layer perpendicular to the c axis; these layers stack together along the c direction merely by van der Waals forces.

(1,4-dabH) 2MnSnS 4: The first thiostannate with integrated Mn 2+ ions in an anionic chain structure

The new thiostannate (1,4-dabH) 2MnSnS 4 (1,4-dab = 1,4-diaminobutane) was synthesized under solvothermal conditions. The compound crystallizes in the non-centrosymmetric space group Fdd2 with a = 22.8124(15) Å, b = 24.7887(16) Å, c = 6.4153(6) Å, Z = 8, and V = 3627.8(5) Å 3. The structure consists of one-dimensional straight anionic chains composed of alternating SnS 4 and MnS 4 tetrahedra sharing common edges. The chains are directed along [001] and are surrounded by the organic cations which form undulated chains along [100] by strong intermolecular N–H⋯N hydrogen bonding interactions. Several S⋯H contacts suggest weak interactions between the anionic chains and the cations. The band gap amounts to 2.9 eV indicating that the compound is a photo-conductor. The compound is stable up to about 190 °C and decomposes in two distinct steps above this temperature.

Crystal Structure of Double Co(NH3)63+Np(V) Malonates Co(NH3)6(NpO2C3H2O4)2A·H2O (A = OH and NO3)

X-ray diffraction analysis of Co(NH3)6(NpO2C3H2O4)2NO3·H2O (I) and Co(NH3)6(NpO2· C3H2O4)2OH·H2O (II) showed that they consist of [NpO2C3H2O4] n n - infinite anionic chains, [Co(NH3)6]3 + cations, NO3 - (I) and OH- (II) anions, and molecules of crystallization water. The anionic chain structure is similar to that in the known compound Co(NH3)6(NpO2C3H2O4)2C3H3O4. Neptunium(V) atoms occur in hexagonal-bipyramidal environment. The coordination capacity of malonate anions is 6, and they simultaneously coordinate three neptunyl(V) cations NpO2 + in the chain.

Novel layered structures constructed from metal(II)–chloranilate monomer compounds

The new copper(II) and cobalt(II) assembled compounds {(G)2[M(CA)2(H2O)2]}n (M = Cu2+, Co2+; H2CA = chloranilic acid; G = 4-hydroxypyridinium cation (4-pyOH2+), 3-hydroxypyridinium cation (3-pyOH2+)) have been synthesized and characterized. In every compound two chloranilate dianions and two water molecules are coordinated to the metal ion making dianionic monomers, [M(CA)2(H2O)2]2−. The coordination environment around the metal ion is a distorted octahedron, where two water molecules sit in a trans position to each other. [M(CA)2(H2O)2]2− anions form anionic layer structures (1, 3) and an anionic chain structure (2) by using hydrogen bonding interactions. The cations are introduced between the {[M(CA)2(H2O)2]2−}l layers or chains, which are supported by both the hydrogen bonding interaction and the electrostatic interaction between the organic cations and the complexes. In compounds 1 and 3, the organic cations are stacked on each other to form a segregated columnar structure between the {[M(CA)2(H2O)2]2−}l layers. On the other hand, in compound 2, the cations are included in a cage as a dimer. The cage is constructed by the chlorine atoms of CA2− dianions of the chains and the organic cations are anchored to the chain by the hydrogen bonding interactions.

The Crystal Structure of Caesium Oxotetrafluorovanadate(V)

The crystal structure of caesium oxotetrafluorovanadate(V) has been solved and refined to an R-value of 0.070 using diffractometer measurements. The cell dimensions are: a = 548.4(2) pm, b = 634.2(2) pm, c = 1403.4(3) pm. The space group is Pnma (No. 62) with four formula units per cell. Each vanadium atom lies 32.6 pm above the base of a tetragonal pyramid with oxygen at the apex (V=O length = 152.9 pm) and fluorine at the four base corners (mean V—F length = 178.8 pm). The tetragonal pyramids are linked by cis-fluorine bridges involving a long V—F bond (V—F(21) = 231.2 pm) to give an anionic chain structure. Structural relationships with other fluorides and oxide-fluorides are noted, and the bond lengths are discussed.