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Hans-Conrad zur Loye

Publications and source records attributed to Hans-Conrad zur Loye.

At least 19 recordsLinked to original sources
PubMed2006

Layered heterometallic iodoplumbate containing a novel Pb3Cu6I16 net: structure and optical properties.

A new heterometallic iodoplumbate was synthesized solvothermally. The complex, [Co(phen)3][Pb3Cu6I16].C2H5OH, contains a novel Pb3Cu6I16 net made up of linked Pb3I11 and Cu6I11 clusters. The clusters form a BN-type layer, where the Pb3I11 and Cu6I11 clusters take the place of B and N. The layers, which are separated by [Co(phen)3]2+ cations, contain cavities in which ethanol molecules are located.

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PubMed2006

Tetrakis[2-(2-pyridyl)pyridinium] tetra-mu3-iodo-hexa-mu2-iodo-dodecaiodohexabismuthate and bis[tris(2,2'-bipyridine)ruthenium(II)] di-mu4-iodo-octa-mu2-iodo-dodecaiodohexabismuthate.

Crystals of the title compounds were grown solvothermally in an ethanol-water solvent mixture using ruthenium triiodide, 2,2'-bipyridine and bismuth triiodide as starting materials. Tetrakis[2-(2-pyridyl)pyridinium] tetra-mu3-iodo-hexa-mu2-iodo-dodecaiodohexabismuthate, (C10H9N2)4[Bi6I22], crystallizes in the triclinic space group P-1 and is the major reaction product. The asymmetric unit of this compound consists of half a centrosymmetric [Bi6I22]4- anion and two independent 2,2'-bipyridinium cations. The minor product of the reaction is bis[tris(2,2'-bipyridine)ruthenium(II)] di-mu4-iodo-octa-mu2-iodo-dodecaiodohexabismuthate, [Ru(C10H8N2)3]2[Bi6I22], which also crystallizes in the triclinic space group P-1. For this compound, the asymmetric unit consists of one full [Ru(2,2'-bipyridine)3]2+ cation and half a centrosymmetric [Bi6I22]4- anion. Although both compounds contain a centrosymmetric [Bi6I22]4- anion, the polyhedral arrangement of the distorted BiI6 octahedra in the two compounds is quite different, and the anion of the latter compound has not previously been observed in iodobismuthate chemistry.

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PubMed2005

Synthesis, structure, and magnetic properties of Sr2NiOsO6 and Ca2NiOsO6: two new osmium-containing double perovskites.

Two new double perovskite oxides, Ca(2)NiOsO(6) and Sr(2)NiOsO(6), have been prepared as polycrystalline powders by solid state synthesis. The two oxides were structurally characterized by variable-temperature powder neutron diffraction. Ca(2)NiOsO(6) was found to adopt a monoclinic structure (P2(1)/n), while Sr(2)NiOsO(6) was found to be tetragonal (I4/m). Magnetic susceptibility measurements indicate that Ca(2)NiOsO(6) orders in a canted antiferromagnetic state at about 175 K while Sr(2)NiOsO(6) orders antiferromagnetically at about 50 K.

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PubMed2005

Crystal structures and magnetic properties of mixed iridium-ruthenium triple perovskites. 1. Ba3MRuIrO9 (M=Lanthanide, Y).

Crystal structures and magnetic properties of Ba3MRuIrO9 (M=lanthanides, Y) were investigated. Rietveld refinements using powder diffraction data indicate that all the compounds crystallize in the 6H-BaTiO3 structure type in space group P63/mmc. Magnetic susceptibility measurements were carried out on each compound. Effective magnetic moments were smaller than values estimated using spin-only moments, which indicate the presence of spin-orbit coupling and strong interactions in the [(Ru0.5Ir0.5)2O9] face-sharing octahedra that contain a disordered mixture of Ru and Ir on a single crystallographic site. Magnetic anomalies were observed for the compounds Ba3PrRuIrO9, Ba3TbRuIrO9, and Ba3NdRuIrO9 at 3.5, 13, and 8 K, respectively.

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PubMed2005

Crystal structures and magnetic properties of mixed iridium-ruthenium triple perovskites. 2. Ba3MRuIrO9 (M=Li, Na, Mg, Ni, Zn, Bi, In).

Crystal structures and magnetic properties of polycrystalline Ba3MRuIrO9 (M1+=Li, Na; M2+=Mg, Ni, Zn; M3+=Bi, In) were investigated. Rietveld refinements of the crystal structures using powder diffraction data indicate that, with the exception of Ba3BiRuIrO9, all compounds crystallize in the 6H-BaTiO3 structure type in space group P63/mmc; Ba3BiRuIrO9 crystallizes in space group C2/c. The 6H-BaTiO3, or triple-perovskite, structure is composed of hexagonal and cubic stacking of [AO3] layers and contains face- and corner-sharing octahedra. The structures in this study contain a disordered mixture of Ir and Ru in the face-sharing octahedra dimers, which are connected via corner-shared MO6 octahedra. Magnetic susceptibility measurements as a function of temperature were carried out on each compound. Effective magnetic moments were smaller than values estimated using spin-only moments, which indicate the presence of spin-orbit coupling and strong interactions in the face-sharing octahedra that contain a disordered mixture of Ru and Ir on a single crystallographic site. Over a broad temperature range, a divergence of the zero-field-cooled and field-cooled data were observed for Ba3MgRuIrO9, Ba3NiRuIrO9, Ba3ZnRuIrO9, and Ba3LiRuIrO9.

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PubMed2005

Non-interpenetrated square-grid coordination polymers synthesized using an extremely long N,N'-type ligand.

Four new, non-interpenetrated square-grid coordination polymers, namely [Mn(L)2(NO3)2]infinity (1), [[Cd(L)2(NO3)2].solvate]infinity (2), [Cd(L)2(NO3)2]infinity (3), and [[Zn(L)2](BF4)2.(C6H6)2.564.(DMF)1.576.(MeOH, H2O)3.454]infinity (4), were synthesized using the new, extremely long N,N'-type ligand: 2,5-bis(4'-(imidazol-1-yl)benzyl)-3,4-diaza-2,4-hexadiene (L). The reaction of Cd(NO3)2 with L leads to two novel structures sharing the same framework composition, [Cd(L)2(NO3)2]infinity, which have different arrangements of L around the metal centers. Both the channel-containing structure and the nonporous structure can be formed by choice of the appropriate solvent system. Moreover, the less stable, channel-containing form readily converts into the more stable, condensed structure upon removal of the guest molecules from the channels.

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PubMed2005

Crystal growth, structural transitions, and magnetic properties of the fluorite-related osmates: Sm3OsO7, Eu3OsO7, and Gd3OsO7.

The Ln3OsO7 (Ln = Sm, Eu, Gd) compounds were grown as single crystals from molten hydroxide fluxes. At temperatures above 235, 330, and 430 K, respectively, the Ln3OsO7 (Ln = Sm, Eu, Gd) compounds exist in the orthorhombic space group Cmcm. When they are cooled below these temperatures, the compounds undergo a structural phase transition from space group Cmcm to P2(1)nb. The structure transition results in a loss of lattice centering, a doubling of the b axis, a distortion of the vertex-shared Os-O chains, and a reduction in the coordination of one of the rare earth cations from 8-fold to 7-fold. Sm3OsO7 and Eu3OsO7 exhibit complex magnetic behavior below about 50 K, and Gd3OsO7 shows a ferromagnetic-like order at 34 K in applied fields of less than 10 kG.

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PubMed2005

Synthesis and characterization of diverse coordination polymers. Linear and zigzag chains involving their structural transformation via intermolecular hydrogen-bonded, interpenetrating ladders polycatenane, and noninterpenetrating square grid from long, rigid N,N'-bidentate ligands: 1,4-bis[(x-pyridyl)ethynyl]benzene (x = 3 and 4).

The long, rigid ligands 1,4-bis[(3-pyridyl)ethynyl]benzene (L1) and 1,4-bis[(4-pyridyl)ethynyl]benzene (L2) were used in the synthesis of 10 new organic-inorganic coordination frameworks, each of them adopting different structural motifs. Synthesis, single-crystal X-ray structure determination, and spectroscopic and thermogravimetric analyses are presented. The reactions between M(NO3)2 x xH2O; M = Cd(II), Cu(II), and Co(II); x = 3-6 and Cu(hfac)2 x H2O [hfac = bis(hexafluoroacetylacetonato)] with L1 afforded the following one-dimensional zigzag chain structures: [Cd(C20H12N2)0.5(NO3)(CH3OH)]n (1, monoclinic, C2/c; a = 7.586(1) A, b = 23.222(1) A, c = 13.572(1) A, beta = 92.824(1), Z = 4); [{Cu(C20H12N2)(NO3)2(CH3OH)} x CH3OH]n (2, orthorhombic, P2(1)2(1)2(1); a = 8.589(1) A, b = 15.766(1) A, c = 17.501(1) A, Z = 4); [Co(C20H12N2)2(NO3)2(H2O)2] (5, triclinic, P1; a = 7.493(1) A, b = 8.948(1) A, c = 14.854(1) A, alpha = 100.427(1), beta = 97.324(1), gamma = 110.901(1), Z = 1); [Cu(C20H12N2)(hfac)2]n (4, monoclinic, C2/c, a = 18.828(1) A, b = 14.671(1) A, c = 13.427(1) A, beta = 90.447(1) degrees, Z = 4). Moreover, the minority phase compound formed from Cu(NO3)2 x 3H2O and L1 yielded a metallocyclic chain structure, [Cu(C20H12N2)(NO3)]n (3, triclinic, P; a = 8.728(1) A, b = 10.018(1) A, c = 11.893(1) A, alpha = 109.991(1), beta = 97.109(1), gamma = 115.542(1), Z = 1). In addition to the dinuclear coordination complex 5, all other polymeric structures (1-4) from L1 are composed of interpenetrating 2D and 3D cross-linked zigzag chains via hydrogen-bonding interactions. The reactions between M(NO3)2 x xH2O; M = Cd(II), Cu(II), and Co(II); x = 3-6 and Cu(hfac)2 x H2O [hfac = bis(hexafluoroacetylacetonato)] and L2 were dependent on the nature of the metal center and resulted in the formation of four different interpenetrating and noninterpenetrating compounds (6-10): [Co(C20H12N2)1.5(NO3)2]n (6, triclinic, P; a = 14.172(1) A, b = 15.795(1) A, c = 18.072(1) A, alpha = 115.380(1), beta = 101.319(1), gamma = 93.427(2), Z = 4), which consists of T-shaped building blocks assembled into three-dimensional interpenetrating polycatenated ladders; [Cd(C20H12N2)2(NO3)2]n (7, monoclinic, I2/a; a = 11.371(1) A, b = 20.311(2) A, c = 15.240(2) A, beta = 100.201(2) degrees, Z = 4), which adopts a two-dimensional noninterpenetrating square-grid motif; [Cu(C20H12N2)(hfac)2]n (8, monoclinic, I2/a; a = 11.371(1) A, b = 20.311(2) A, c = 15.240(2) A, beta = 100.201(2) degrees, Z = 4), composed of three sets of distinct one-dimensional linear chains; [Cu(C20H12N2)(EtOH)(NO3)2] [Cu(C20H12N2)1.5(NO3)2] x 2EtOH (9, triclinic, P; a = 12.248(2) A, b = 13.711(3) A, c = 18.257(4) A, alpha = 108.078(4) degrees, beta = 97.890(4) degrees, gamma = 103.139(5) degrees, Z = 2) and [Cu(C20H12N2)(MeOH)(NO3)2] [Cu(C20H12N2)1.5(NO3)2] x 2MeOH (10, triclinic, P; a = 12.136(1) A, b = 13.738(2) A, c = 17.563(3) A, alpha = 107.663(3) degrees, beta = 94.805(4) degrees, gamma = 104.021(4) degrees, Z = 2). Both 9 and 10 stack into infinite interpenetrating ladders through bundles of infinite chains and are described in our preliminary communication.

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PubMed2005

Crystal growth and magnetic properties of lanthanide-containing osmium double perovskites, Ln2NaOsO6 (Ln = La, Pr, Nd).

A series of double perovskite oxides, Ln(2)NaOsO(6) (Ln = La, Pr, Nd), has been prepared as single crystals from acidic molten NaOH. All three oxides crystallize in the monoclinic space group P2(1)/n (Glazer tilt system #10, a(-)a(-)b(+)), forming a 1:1 ordered rock salt lattice of the Na(+) and Os(5+) cations. Magnetic susceptibility measurements show evidence of antiferromagnetic correlations in La(2)NaOsO(6) and of a spin-flop transition from an antiferromagnetic to ferromagnetic-like state in both Pr(2)NaOsO(6) and Nd(2)NaOsO(6).

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PubMed2005

A noninterpenetrated 1D molecular ladder and 2D butterfly network: effect of positional isomerism of semirigid bis(pyridylmethyl)pyromellitic diimide ligands on the architecture of their metal(II) complexes.

Three new complexes [Cd(4-pmpmd)1.5 (NO3)2] x CHCl3 (1), [Cd(3-pmpmd)1.5 (NO3)2] x EtOH (2), and [Zn(3-pmpmd)1.5 (NO3)2] x MeOH (3) (3- or 4-pmpmd = N,N'-bis(3- or 4-pyridylmethyl)pyromellitic diimide) containing T-shaped building blocks have been obtained from reactions between the long semirigid ligands 3- or 4-pmpmd and either cadmium or zinc nitrate. 1 forms noninterpenetrated 1D molecular ladders that are linked via multiple, complementary intermolecular C-H...O hydrogen bonds that effect the 3D alignment. 2 and 3 are isostructural and feature a noninterpenetrated 2D butterfly-shaped network with (6,3) topology. Multiple intermolecular C-H...O hydrogen bonds exist between the 2D layers and generate the 3D framework. The structural differences between 1 and 2 or 3 are attributed to the different conformations adopted by the ligands, which illustrate the influence of positional isomerism on the resultant supramolecular architectures of metal complexes.

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PubMed2004

New Ag(I)-containing coordination polymers generated from multidentate Schiff-base ligands.

The coordination chemistry of the multidentate Schiff-base ligands 2,5-bis(3-methylpyrazinyl)-3,4-diaza-2,4-hexadiene (L5) and 2,5-bis(pyrazinyl)-3,4-diaza-2,4-hexadiene (L6) with inorganic Ag(I) salts has been investigated. Six new Ag(I)-coordination polymers were prepared by solution reactions and fully characterized by infrared spectroscopy, elemental analysis, thermogravimetric analysis, and single-crystal X-ray diffraction. [Ag(L5)]ClO(4).0.5CH(3)OH (1, orthorhombic, Fdd2; a = 20.0896(11) A, b = 48.224(3) A, c = 7.8432(4) A, Z = 16), [Ag(L5)]PF(6).0.5CH(3)OH (2, orthorhombic, Fdd2; a = 20.7255(11) A, b = 46.166(2) A, c = 8.4332(4) A, Z = 16), [Ag(L5)]SbF(6).0.5CH(3)OH (3, orthorhombic, Fdd2; a = 21.5481(11) A, b = 45.196(2) A, c = 8.7331(4) A, Z = 16), and [Ag(L5)](BF(4)).0.5CH(3)OH (4, orthorhombic, Fdd2; a = 19.8897(11) A, b = 48.358(3) A, c = 7.7491(5) A, Z = 16) were obtained by combination of L5 with AgClO(4).xH(2)O, AgPF(6), AgSbF(6), and AgBF(4), respectively, in a methylene chloride/methanol mixed solvent system. Compounds 1-4 are isostructural and feature noninterpenetrating three-dimensional zeolite-like networks. [Ag(4)(L6)(4)](PF(6))(4).CHCl(3) (5, tetragonal, Pc2; a = 16.1067(3) A, b = 16.1067(3) A, c = 14.4935(5) A, Z = 2) was generated from the reaction of L6 with AgPF(6) in a chloroform/ethanol mixed solvent system. It forms with a unique one-dimensional nanometer-tube that can be considered a new polymeric motif based on the [AgN5] coordination sphere. The tubes are square with crystallographic dimensions of 10.3 x 10.0 A. The tubes are further linked together through weak interpolymer C-H...F hydrogen bonding interactions into a novel H-bonded three-dimensional network containing square tubes, in which uncoordinated PF(6)(-) counterions and chloroform guest molecules are located. Compound 6 ([Ag(mu-C(6)H(6)N(2)O)](SO(3)CF(3)), monoclinic, P2(1)/c; a = 12.3435(6) A, b = 20.3548(10) A, c = 9.0861(5) A, Z = 8) was obtained by combination of AgSO(3)CF(3) and L6 in a methylene chloride/benzene mixed solvent system. In 6, 2-acetylpyrazine, which was generated from the hydrolysis reaction of L6 in the presence of CF(3)SO(3)(-) and a small quantity of water in solvent, chelates the Ag(I) centers through the carbonyl O-donor, and the vicinal pyrazine N-donor, furthermore, uses the para-N atoms to link other Ag(I) centers into one-dimensional zigzag chains. The triflate anions link the chains into a three-dimensional network by somewhat long Ag.O contacts.

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PubMed2004

Assembly of large simple 1D and rare polycatenated 3D molecular ladders from T-shaped building blocks containing a new, long N,N'-bidentate ligand.

Molecular ladders [Co(2)(nbpy4)(3)(NO(3))(4)]*solvents and [Cd(2)(nbpy4)(3)(NO(3))(4)](nbpy4 =N,N'-bis-(4-pyridinylmethylene)-1,5-naphthalenediamine) were synthesized via self-assembly; the former is a large, simple, noninterpenetrated 1D ladder that contains guest solvent molecules between the rungs, while the latter exists as 1D ladders in a rare four-fold interlocked 3D structure.

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PubMed2004

Exceptionally stable, hollow tubular metal-organic architectures: synthesis, characterization, and solid-state transformation study.

An effective solvothermal procedure has been developed to synthesize the new three-dimensional metal-organic framework, [ZnF(AmTAZ)].solvents, using either 3-amino-1,2,4-triazole (AmTAZ) or 3-amino-1,2,4-triazole-5-carboxylic acid (AmTAZAc) and a choice of several Zn(II) salts as starting materials. The three-dimensional structure displays open-ended, hollow nanotubular channels that are formed by hexanuclear metallamacrocyclic Zn(6)F(6)(AmTAZ)(6) rings. The framework integrity is maintained to 350 degrees C, at which point most of the guest solvent molecules have been removed, as evidenced by single-crystal X-ray analyses, (1)H solid-state NMR, and TGA measurements. At higher temperatures, the framework is converted either to zinc oxide (ZnO) when heated in air or to zinc cyanamide (ZnCN(2)) when heated in an inert atmosphere. In both cases, the as-grown, rodlike crystal shape is maintained during the solid-state transformation, suggesting a possible route for preparing one-dimensional crystalline nanomaterials.

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PubMed2004

Crystal growth and structure determination of barium rhodates: stepping stones toward 2H-BaRhO3.

Single crystals of two new barium rhodates were grown from a molten potassium carbonate flux. The new rhodates, Ba(11)Rh(10)O(30) and Ba(32)Rh(29)O(87), are structurally related to the 2H-hexagonal perovskite structure and are characterized by pseudo one-dimensional chains of alternating face-sharing trigonal prisms and octahedra. The structures of Ba(11)Rh(10)O(30) and Ba(32)Rh(29)O(87) were solved using the 4D superspace group approach in Jana2000. Ba(11)Rh(10)O(30), with a repeat of nine RhO(6) octahedra followed by one RhO(6) trigonal prism, contains the longest chain sequence of face-sharing octahedra known for this 2H-perovskite related family of oxides. A structural analysis of these two compounds revealed clear trends in metal-metal distances and octahedral heights not previously identified for this family of oxides. The application of these trends toward the structure of the all-octahedra-containing end member of the structural series, the hypothetical 2H-BaRhO(3), enabled a prediction of its rhodium-rhodium distance, octahedral height, and lattice parameters.

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PubMed2003

(NaLa2)NaPtO6: The first 2H-perovskite related oxide with a rare earth cation on the A-site.

Crystals of (NaLa(2))NaPtO(6) were grown in an acidic ("wet") NaOH flux. (NaLa(2))NaPtO(6) forms in a 2H-perovskite related structure type and contains mixed cation (Na/La) occupancy on the A-site. The crystal was a rhombohedral obverse-reverse twin, and it crystallizes in the space group R3c (hexagonal setting) with lattice parameters of a = 9.5031(2) A and c = 11.4625(5) A. (NaLa(2))NaPtO(6) is the first example of an m = 0, n = 1 (A(3)A'BO(6)) member of the A(3n)+3m)A'(n)B(3m+n)O(9m+6n) family of oxides where either a lanthanide or a sodium cation occupies the A-site.

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PubMed2003

Formation of dinuclear, macrocyclic, and chain structures from HgI(2) and a semirigid benzimidazole-based bridging ligand: an example of ring-opening supramolecular isomerism.

The reactions of HgI(2) with the semirigid ditopic ligand 1,3-bis(benzimidazol-1-ylmethyl)-2,4,6-trimethylbenzene (bbimms) afforded three new complexes, [Hg(2)(mu-I)(2)I(2)(bbimms)] (1), [Hg(2)I(4)(bbimms)(2)] (2), and catena-poly[HgI(2)(bbimms)] (3). The ligand and all complexes have been structurally characterized by single-crystal X-ray diffraction. 1 is a triply bridged dinuclear complex comprised of two Hg(II) ions, one bridging ligand, two bridging I(-) anions, and two terminal I(-) anions. 2 is a dinuclear metallamacrocycle comprised of two Hg(II) ions, two bridging ligands, and four terminal I(-) anions, while 3 is a helical chain with the repeating unit of HgI(2)(bbimms). 2 and 3 can be classified as supramolecular isomers, and both are related to the triply bridged precursor 1 via the addition of one more ligand in a ring-opening process.

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