Search results for "Isostructural"
showing 10 items of 158 documents
Different structural destinations: comparing reactions of [CuBr2(3-Brpy)2] crystals with HBr and HCl gas
2011
Reaction of green crystalline solid trans-[CuBr2(3-Brpy)2] 1 (3-Brpy = 3-bromopyridine) with HBr (aq) vapour yields brown crystalline salt (3-BrpyH)2[CuBr4] 2 with quantitative conversion. Notably 2 adopts a different crystal structure to the three mutually isostructural compounds (3-XpyH)2[CuCl4] (X = Cl, Br) and (3-BrpyH)2[CuBr2Cl2] which result from reaction with HCl. Crystalline product 2 has been characterised by X-ray powder diffraction and its conversion back to 1 at 370–400 K has been followed in situ by synchrotron X-ray powder diffraction. Crystalline 1 and 2 are further notable for the presence of intermolecular C–Br⋯Br–Cu halogen bonds and (only in the case of 2) N–H⋯Br–Cu hydro…
Non-Isomorphic Chlorine—Bromine Substitution in the Copper(I) Halideπ-Complexes with 1-Allyl-4-aminopyridinium
2003
By alternating-current electrochemical synthesis crystals of {Cu[H2NC5H4N(C3H5)]Br2}˙H2O (I), {Cu[H2NC5H4N(C3H5)]Br0.65Cl1.35}˙H2O (II) and {Cu[H2NC5H4N(C3H5)]Cl2} (III) π-complexes have been obtained and structurally investigated. The I and II compounds are isostructural and crystallize in a monoclinic sp. gr. P21/c, I: a = 7.359(2)A, b = 12.3880(6)A, c = 13.637(3)A, β = 107.03(1)°, V = 1188.7(4)A3, Z = 4 for C8H13N2OBr2Cu composition, R = 0.0293 for 2140 reflections. II: a = 7.2771(6)A, b = 12.3338(3)A, c = 13.4366(7)A, β = 107.632(2)°, V = 1149.3(1)A3, Z = 4 for C8H13N2Br0.65Cl1.35Cu composition, R = 0.0463 for 2185 reflections. Metal and halogen atoms form centrosymmetric Cu2X4 dimers. …
Oxalate‐Based 3D Chiral Magnets: The Series [Z II (bpy) 3 ][ClO 4 ][M II Fe III (ox) 3 ] (Z II = Fe, Ru; M II = Mn, Fe; bpy = 2,2'‐Bipyridine; ox = O…
2005
The synthesis, structure, and physical properties of the oxalate-based molecular magnets with the formula [ZII(bpy)3][ClO4][MIIFeIII(ox)3] (ZII = Fe, Ru; MII = Mn, Fe; bpy = 2,2'-bipyridine; ox = oxalate dianion) are presented here. All compounds are isostructural and crystallize in the chiral cubic space group P4132, and contain three-dimensional dimetallic networks formed by alternating MII and MIII ions that are connected by oxalate anions. These compounds exhibit strong antiferromagnetic interactions that give rise to magnetic ordering as ferrimagnets or weak ferromagnets, with critical temperatures of up to 20 K, which is twice as high as those found for the isostructural magnets based…
Hexacyanocobaltate(III) Anions as Precursors of Co(II)−Ni(II) Cyano-Bridged Multidimensional Assemblies: Hydrothermal Syntheses, Crystal and Powder …
2005
Three novel cyanide-bridged heterobimetallic coordination polymers have been synthesized by hydrothermal routes, in superheated water solutions, by using K3[Co(CN)6], NiCl2.6H2O, and alpha-diimine ligands: [Ni(CN)4Co(phen)] (1; phen = 1,10-phenanthroline), [Ni(CN)4Co(2,2'-bipy)] (2; 2,2'-bipy = 2,2'-bipyiridine), and [Ni(CN)4Co(2,2'-bipy)2] (3). The isostructural compounds 1 and 2 contain a two-dimensional network with Co(II) centers octahedrally coordinated by one chelating 2,2'-bipy ligand and four cyanide groups of four distinct [Ni(CN)4]2-, through crystallographically equivalent, bridging units. Compound 3 contains one-dimensional zigzag chains in which the Co(II) ion is coordinated by…
Efficient Diffusion-Controlled Ligand Exchange Crystal Growth of Isostructural Inorganic–Organic Halogenidorhodates(III): The Missing Hexaiodidorhoda…
2015
The monohydrates of piperazine-1,4-diium hexabromidorhodate(III) bromide and hexaiodidorhodate(III) iodide were obtained by a diffusion-controlled ligand exchange crystal growth method using a hydrochloric acid solution of rhodium(III) chloride trihydrate and piperazine, dissolved in hydrobromic and hydroiodic acid, respectively, separated by a layer of hydrohalic acid. Both inorganic–organic hybrids are defined by the general formula (C4H12N2)2[RhX6]X·H2O (X = Br, 1 or I, 2). They both crystallize in the orthorhombic Pnma space group, and they are isostructural with an isostructurality index above 95%. The cationic building blocks—piperazine-1,4-diium ions and the inorganic components—slig…
Influence of Cl/Br substitution on the stereochemical peculiarities of copper(I) pi-complexes with the 1-allyl-2-aminopyridinium cation.
2003
By using alternating-current electrochemical synthesis, crystals of the CuI π-complexes bis(1-allyl-2-aminopyridinium) di-μ-chloro-bis[chlorocopper(I)], (C8H11N2)2[Cu2Cl4] or [H2NC5H4NC3H5][CuCl2], and bis(1-allyl-2-aminopyridinium) di-μ-(chloro/bromo)-bis[(chloro/bromo)copper(I)], (C8H11N2)2[Cu2Br2.2Cl1.8] or [H2NC5H4NC3H5][CuBr1.10Cl0.90], have been obtained and structurally investigated. In each of the isostructural (isomorphous) compounds, the distorted tetrahedral Cu environment involves three halide atoms and the C=C bond of the ligand. Both compounds reside on inversion centres, and the dimeric [Cu2 X 4·2H2NC5H4NC3H5] units are bonded into a three-dimensional structure by N—H...X hyd…
Chiral Molecular Magnets: Synthesis, Structure, and Magnetic Behavior of the Series [M(L-tart)] (M = MnII, FeII, CoII, NiII;L-tart = (2R,3R)-(+)-tart…
2006
A new series of layered magnets with the formula [M(L-tartrate)] (M = Mn(II), Co(II), Fe(II), Ni(II); L-tartrate = (2R,3R)-(+)-tartrate) has been prepared. All of these compounds are isostructural and crystallize in the chiral orthorhombic space group I222, as found by X-ray structure analysis. Their structure consists of a three-dimensional polymeric network in which each metal shows distorted octahedral coordination bound to four L-tartrate ligands, two of which chelate through an alcohol and a carboxylate group and the other two bind terminally through a monodentate carboxylate group. The chirality of the ligand imposes a Delta conformation on all metal centers. Magnetically, the paramag…
Isostructural compartmentalized spin-crossover coordination polymers for gas confinement
2016
[EN] Here we present two FeII coordination polymers that possess discrete compartments suitable for CO2 physisorption despite the lack of permanent channels. The two crystalline materials, of general formula [Fe(btzbp)3](X)2 (X = ClO4 or BF4), present voids of ca. 250 Å3, which each can accommodate up to two CO2 molecules. The abrupt spin transition can be modified upon CO2 sorption, and different magnetic behaviour is observed depending on the number of molecules sorbed.
Organic/inorganic molecular conductors based upon perylene and Lindquist-type polyoxometalates
2001
The preparation, structures and physical properties of the organic/inorganic radical salts based upon perylene (per) and Lindquist type polyoxometalates (POMs) are reported. Three new hybrid salts have been prepared: (per)5[Mo6O19] (1), (per)5[W6O19] (2), and (per)5[VW5O19] (3). Only structures 1 (P, Z = 2) and 3 (P, Z = 2) were fully determined as compound 2 was found to have unit cell parameters practically identical to 1 and, therefore, is considered isostructural with the latter. The structures consist of interpenetrated organic and mixed organic/inorganic layers in the ac plane alternating along the a direction. The organic layers present a novel packing mode of the perylene molecules …
Isoreticular two-dimensional magnetic coordination polymers prepared through pre-synthetic ligand functionalization
2018
Chemical functionalization is a powerful approach to tailor the physical and chemical properties of two-dimensional (2D) materials, increase their processability and stability, tune their functionalities and, even, create new 2D materials. This is typically achieved through post-synthetic functionalization by anchoring molecules on the surface of an exfoliated 2D crystal, but it inevitably alters the long-range structural order of the material. Here we present a pre-synthetic approach that allows the isolation of crystalline, robust and magnetic functionalized monolayers of coordination polymers. A series of five isostructural layered magnetic coordination polymers based on Fe(ii) centres a…