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1.	Abu-Youssef, Morsy A.M., et al. (author) 1D, 2D and 3D cadmium(II) polymeric complexes with quinoline-4-carboxylato anion, quinazoline and 2,5-dimethylpyrazine 2006 In: Polyhedron. - : Elsevier BV. - 0277-5387. ; 25:5, s. 1187-1194 Journal article (peer-reviewed)abstract Three new cadmium(II) complexes, namely [Cd(Qux)2(H2O)]n (1), [Cd(Quz)2(N3)2]n (2) and [Cd(dmpz)(N3)2]n (3) (Qux = quinoline-4-carboxylato anion, Quz = quinazoline, dmpz = 2,5-dimethylpyrazine), have been synthesized and characterized by spectroscopic and crystallographic methods. The structure of 1 contains CdO6 slightly distorted octahedral geometry around the Cd(II) atoms, axialy coordinated to two bridging water molecules forming the 1D chain and four oxygen atoms from four different μ-O,O′-bridging caboxylato groups of (Qux) in the equatorial plane. The 1D chains are further held together through hydrogen bonds between the μ-aqua molecule and the meta non-coordinated nitrogen atom of the quinoline moiety. In complex 2, two quinazoline ligands are linked to the central Cd(II) ion in a trans position through the meta hetero nitrogen atom and di(EE), (μ1,3-N3) groups and show a two dimensional (2D) topology. In complex 3 the central cadmium(II) atom is simultaneously coordinated to di(EE), (μ1,3-N3) groups (NCdN, 180.0°) forming a sheet structure in the bc plane and further bridging μ-N,N′-dimethylpyrazine ligand in the a-direction (NCdN, 180.0°) giving rise to a 3D network structure. The IR spectra of the three complexes were measured and they confirm the X-ray structural data.
2.	Abu-Youssef, Morsy A.M., et al. (author) 1D and 2D FeII Azide Coordination Polymers with Ferromagnetic Canting 2008 In: European Journal of Inorganic Chemistry. - : Wiley. - 1434-1948 .- 1099-0682. ; 2008:1, s. 112-118 Journal article (peer-reviewed)abstract The two compounds [FeII(pyridine)2(N3)2(H2O)] (1) and [FeII(4-acetylpyridine)2(N3)2] (2) were prepared. The X-ray crystal structures show end-to-end (EE) bridging azides in both cases with a 1D Fe-NNN-Fe chain for 1 and a 2D Fe-NNN-Fe net in 2. Both compounds show similar magnetic behaviour where the high-temperature data are consistent with antiferromagnetic couplings and the low-temperature data indicate ferrimagnetic ordering based on spin canting at 20 and 45 K. Compound 2 also shows a hysteresis loop. These findings are compared to the related 3D coordination polymer [Fe(N3)2(4,4'-bipyridine)]. According to network analyses the latter compound was shown to contain the new uninodal six-connected-network topology (510 · 64 · 7)-jsm.
3.	Abu-Youssef, Morsy A.M., et al. (author) A unique example of a high symmetry three- and four-connected hydrogen bonded 3D-network 2006 In: Chemical Communications. - : Royal Society of Chemistry (RSC). - 1364-548X .- 1359-7345. ; 2006:10, s. 1082-1084 Journal article (peer-reviewed)abstract We present a three- and four-connected 3D-net based on 4-aminopyridine coordinated to Ag(I) and hydrogen bonded to nitrate with the unusual, high symmetry, topology (83)(86)2-tfa.
4.	Abu-Youssef, Morsy A. M., et al. (author) Molecular, supramolecular structures combined with hirshfeld and dft studies of centrosymmetric m(Ii)-azido {m=ni(ii), fe(ii) or zn(ii)} complexes of 4-benzoylpyridine 2021 In: Symmetry. - : MDPI AG. - 2073-8994. ; 13:11 Journal article (peer-reviewed)abstract The supramolecular structures of the three metal (II) azido complexes [Fe(4bzpy)4 (N3 )2 ]; 1, [Ni(4bzpy)4 (N3 )2 ]; 2 and [Zn(4bzpy)2 (N3 )2 ]n; 3 with 4-benzoylpyridine (4bzpy) were presented. All complexes contain hexa-coordinated divalent metal ions with a slightly distorted octahedral MN6 coordination sphere. Complexes 1 and 2 are monomeric with terminal azido groups while 3 is one-dimensional coordination polymer containing azido groups with µ(1,1) and µ(1,3) bridging modes of bonding. Hirshfeld analysis was used to quantitatively determine the different contacts affecting the molecular packing in the studied complexes. The most common interactions are the polar O … H and N … H interactions and the hydrophobic C … H contacts. The charges at the M(II) sites are calculated to be 1.004, 0.847, and 1.147 e for complexes 1–3, respectively. The degree of asymmetry is the highest in the case of the terminal azide in complexes 1 and 2 while was found the lowest in the µ(1,1) and µ(1,3) azide bonding modes in the Zn(II) complex 3. These facts were further explained in terms of atoms in molecules (AIM) topological parameters.
5.	Abu-Youssef, Morsy A.M., et al. (author) NEW Ag(I) COMPOUNDS AND THEIR USE IN PHARMACEUTICAL COMPOSITIONS 2007 Other publication (other academic/artistic)
6.	Abu-Youssef, Morsy A. M., et al. (author) New Polymeric Manganese Azide Derivatives with Quinazoline 2005 In: European Journal of Inorganic Chemistry. - 1434-1948 .- 1099-0682. ; 2005:22, s. 4659 - 4664 Journal article (peer-reviewed)abstract Two new polymeric derivatives of the (azido)MnII system with formula [Mn(H2O)(μ-N3)(N3)(quinaz)2]n (1) and [Mn(μ-N3)2(quinaz)2]n (2) (quinaz = quinazoline) have been structurally and magnetically characterised. Compound 1 crystallises in the triclinic system, space group P-1, and consists of 1D chains with single end-to-end azido bridges. These chains give a two-dimensional supramolecular arrangement by means of H-bond interactions. Compound 2 crystallises in the monoclinic system, space group C2/c, and contains a square alternating 2D network bridged by azido ligands in the end-to-end coordination mode. Compound 2 exhibits some unusual features, such as the unprecedented linear coordination of the azido bridge. Magnetic analysis reveals moderate antiferromagnetic coupling, with J values in good agreement with the expected range, as a function of the Mn-N-N bond angles.
7.	Abu-Youssef, Morsy A.M., et al. (author) Synthesis, a case of isostructural packing, and antimicrobial activity of silver(I)quinoxaline nitrate, silver(I)(2,5-dimethylpyrazine) nitrate and two related silver aminopyridine compounds 2006 In: Dalton Transactions. - : Royal Society of Chemistry (RSC). - 1477-9226 .- 1477-9234. ; 2006:21, s. 2542-2550 Journal article (peer-reviewed)abstract The synthesis and low temperature crystal structures of [Ag(quinoxaline)]n(NO3)n, 1, [Ag(2,5-dimethylpyrazine)(NO3)]n, 2 and [Ag4(3-aminopyridine)4(NO3)4]n 3 are presented. The quinoxaline compound forms a 1D coordination polymer with the characteristic linear 2-coordination figure of silver(I), the NAgN angle being 164.2(1)°, and only weak silvernitrate interactions. In addition there is an interaction giving pairs of parallel chains as the main structural theme. The 2,5-dimethylpyrazine compound has approximately trigonal-planar coordination, also binding one nitrate at the relatively short AgO distances 2.444(3)Å and 2.484(3)Å, respectively, for the two crystallographically different silver atoms. This also results in a 1D coordination polymer that, despite the large differences in the Ag(I) coordination environment, is isostructural with 1. [Ag4(3-aminopyridine)4(NO3)4]n 3 forms a 2D coordination polymer by bridging nitrate ions. The antimicrobial activity of 13, and also of [Ag3(2-aminopyridine)4](NO3)3, 4 was screened for 13 different pathogens and substantial activity was shown for 1 against Escherichia coli and Pseudomonas aeruginosa (MIC 4 µg cm3) and somewhat lower activity was registered against Sarcina lutea and Salmonella typhi for 1, Bordetella bronchiseptica for 2, Salmonella typhi and Pseudomonas aeruginosa for 3, and Escherichia coli and Shigella sonnie for 3 (MIC 8 µg cm3). Only low activity was shown against the yeast Candida albicans for 1, 2 and 4 whereas no activity against this pathogen was registered for 3.
8.	Abu-Youssef, Morsy A.M., et al. (author) Synthesis and Structure of Silver Complexes with Nicotinate-Type Ligands Having Antibacterial Activities against Clinically Isolated Antibiotic Resistant Pathogens 2007 In: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 46:15, s. 5893-5903 Journal article (peer-reviewed)abstract The synthesis and low-temperature X-ray crystal structures of five new silver complexes, [Ag2-μ-O,O'(2-aminonicotinium)2(NO3)2]n (7), [Ag(isonicotinamide)2-μ-O,O'(NO3)]2 (8), [Ag(ethyl nicotinate)2](NO3) (9), [Ag(ethyl isonicotinate)2(NO3)] (10), and [Ag(methyl isonicotinate)2(H2O)](NO3) (11), are presented and fully characterized by spectral and elemental analysis. The antimicrobial activities of these complexes were screened using 12 different clinical isolates belonging to four pathogenic bacteria, S. aureus, S. pyogenes, P. mirabilis, and Ps. Aeruginosa, all obtained from diabetic foot ulcers. These tested bacteria were resistant for at least 10 antibiotics commonly used for treatment of diabetic foot ulcers. Compounds 7 and 8 had considerable activity against Ps. Aeruginosa (MIC values 2-8 µg/mL), compound 9 against S. aureus (MIC 4-16 µg/mL) and S. pyogenes (MIC 2-4 µg/mL), and also 9 and 11 against P. mirabilis (MIC 1-16 µg/mL). All complexes were non-toxic for daphnia at concentrations above 512 µg/mL overnight.
9.	Abu-Youssef, Morsy A. M., et al. (author) Synthesis, Crystal Structure, Quantum Chemical Calculations, DNA Interactions, and Antimicrobial Activity of [Ag(2-amino-3-methylpyridine)2]NO3 and [Ag(pyridine-2-carboxaldoxime)NO3] 2010 In: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 49:21, s. 9788-9797 Journal article (peer-reviewed)abstract [Ag(2-amino-3-methylpyridine)2]NO3 (1) and [Ag(pyridine-2-carboxaldoxime)NO3] (2) were prepared from corresponding ligands and AgNO3 in water/ethanol solutions, and the products were characterized by IR, elemental analysis, NMR, and TGA. The X-ray crystal structures of the two compounds show that the geometry around the silver(I) ion is bent for complex 1 with nitrate as an anion and trigonal planar for complex 2 with nitrate coordinated. ESI-MS results of solutions of 2 indicate the independent existence in solution of the [Ag(pyridine-2-carboxaldoxime)]+ ion. The geometries of the complexes are well described by DFT calculations using the ZORA relativistic approach. The compounds were tested against 14 different clinically isolated and four ATCC standard bacteria and yeasts and also compared with 17 commonly used antibiotics. Both 1 and 2 exhibited considerable activity against S. lutea, M. lutea, and S. aureus and against the yeast Candida albicans, while 2-amino-3-methylpyridine is slightly active and pyridine-2-carboxaldoxime shows no antimicrobial activity. In addition, the interaction of these metal complexes with DNA was investigated. Both 1 and 2 bind to DNA and reduce its electrophoretic mobility with different patterns of migration, while the ligands themselves induce no change.
10.	Abu-Youssef, Morsy A.M., et al. (author) Synthesis, Structure, and Magnetic Behavior of Two New 1D Polymeric Manganese Azido Complexes 2006 In: European Journal of Inorganic Chemistry. ; 2006:16, s. 3177-3184 Journal article (peer-reviewed)abstract Two new MnII one-dimensional compounds with formulae [Mn(μ-N3)2(pyzamid)2]n (1) and [Mn2(3-ampy)4(μ-N3)2(N3)2(H2O)2]n, (2) (pyzamid = pyrazineamide and 3-ampy = 3-aminopyridine) were structurally and magnetically characterized. Compound 1 crystallizes in the monoclinic system, P2/c space group, and polymerizes through double end-on azido bridges giving 1D chains with the MnII atoms in a MnN6 environment. Compound 2 crystallizes in the triclinic system, P-1 space group, and consists of alternate [Mn(3-ampy)2(μ-N3)2(N3)2] and [Mn(3-ampy)2(μ-N3)2(H2O)2] octahedrons (MnN6 - MnN4O2 environments), linked by single end-to-end azido bridges. Both chains show very uncommon topologies. Attemps to obtain manganese/azido derivatives with the qux = quinoline-4-carboxylato anion gave the recently reported compound [Mn(μ-qux)2(μ-H2O)]n (3), which consists of a chain with only carboxylato and aqua bridges with the MnII atoms in a MnO6 slightly distorted octahedron. In good agreement with the expected behavior, magnetic susceptibility measurements show weak ferromagnetic interactions for 1, whereas compound 2 exhibits moderate antiferromagnetic coupling.
11.	Amer, Adel, et al. (author) A regio- and stereo-controlled approach to triazoloquinoxalinyl C-nucleosides 2010 In: Carbohydrate Research. - : Elsevier BV. - 0008-6215 .- 1873-426X. ; 345:17, s. 2474-2484 Journal article (peer-reviewed)abstract The synthesis of a new series of acyclic triazoloquinoxalinyl C-nucleosides and their transformation to their cyclic analogs are described following protection, activation, and deprotection with subsequent intramolecular nucleophilic substitution protocol. The antibacterial potency of the new compounds was determined using an inhibition zone diameter test. The results show that 3a and 2b exhibit good activity against Escherichia coli and Candida albicans. On the other hand, the cyclic mesylated C-nucleoside 13 showed activity against the Gram-positive bacteria (Staphylococcus aureus) and antifungal activity against C. albicans.
12.	Amirnasr, Mehdi, et al. (author) Synthesis and characterization of Co(II) and Ni(II) complexes of 2,5-diphenyl-3,4-bis(2-pyridyl)-cyclopentadienone (L). X-ray crystal structures of CoLCl2.0.5CH3CN and NiLBr2.CHCl3 2010 In: Polyhedron. - : Elsevier BV. - 0277-5387. ; 29:3, s. 985-990 Journal article (peer-reviewed)abstract The preparation and properties of [M(chelate)X2] complexes are reported, where M = Co(II) or Ni(II), chelate = 2,5-diphenyl-3,4-bis(2-pyridyl)cyclopentadienone and X = Cl or Br. These complexes have been characterized by elemental analyses and spectroscopic methods. The crystal and molecular structures of CoLCl2·0.5CH3CN (1) and NiLBr2·CHCl3 (4) have been determined by X-ray crystallography. Compound (1) crystallizes in the triclinic space group P-1, different from that of CoLCl2 (monoclinic space group P21/c) that we have reported previously. Compound (4) crystallizes in the monoclinic space group P21/n. Both CoLCl2 and NiLBr2 complexes are pseudo-tetrahedral, and utilization is made of the electronic and vibrational spectra in the structural diagnosis of CoLBr2 and NiLCl2.
13.	Amirnasr, Mehdi, et al. (author) Synthesis, characterization, and single crystal X-ray structures of [CoIII(acacen)(thioacetamide)2]ClO4 and [CoIII((BA)2en)(thioacetamide)2]PF6 - Solvatochromic properties of [CoIII(acacen)(thioacetamide)2]ClO4 2005 In: Canadian Journal of Chemistry. - 0008-4042 .- 1480-3291. ; 83:12, s. 2073-2081 Journal article (peer-reviewed)abstract The trans-[CoIII(acacen)(ta)2]ClO4 (1) and trans-[CoIII((BA)2en)(ta)2]PF6 (2) complexes, where H2acacen = bis(acetylacetone)ethylenediimine, H2(BA))2en = bis(benzoylacetone)ethylenediimine, and ta = thioacetamide, have been synthesized by a solid-state method, and characterized by elemental analyses, IR, UV-vis, and 1H NMR spectroscopy. The crystal and molecular structures of 1 and 2 were determined by X-ray crystallography. Both compounds crystallize in the monoclinic space group P2/n. The ClO4 and PF6 ions are both disordered, ClO4 on a twofold axis in 1 and PF6 on an inversion center in 2. Also bridging N-CH2-CH2-N is disordered in both compounds. The octahedral coordination of Co(III) is slightly distorted in both cases. The thioacetamide ligands are S-bonded and occupy the axial position. The IR, UV-vis, and 1H NMR spectra of the two complexes and their solvatochromic properties are also discussed. The longest wavelength absorption that appears at 517 nm for 1 and at 528 nm for 2 in chloroform is solvent dependent, and is assigned as a metal-mediated ligand-to-ligand charge transfer (LLCT).
14.	Andersen, Leif, et al. (author) The structure of K2TeO3 - an experimental and theoretical study 1989 In: Acta Cryst B. - 0108-7681. ; 45:4, s. 344-348 Journal article (peer-reviewed)
15.	Angenete, Johan, 1971, et al. (author) Oxidation of simple and Pt modified aluminide diffusion coatings on Ni based superalloys - I. Oxide scale microstructure 2003 In: Oxidation of Metals. ; 60:1-2, s. 47-82 Journal article (peer-reviewed)
16.	Bella, M., et al. (author) Reaction of selected carbohydrate aldehydes with benzylmagnesium halides: benzyl versus o-tolyl rearrangement 2014 In: Beilstein Journal of Organic Chemistry. - : Beilstein Institut. - 1860-5397. ; 10, s. 1942-1950 Journal article (peer-reviewed)abstract The Grignard reaction of 2,3-O-isopropylidene-alpha-D-lyxo-pentodialdo-1,4-furanoside and benzylmagnesium chloride (or bromide) afforded a non-separable mixture of diastereomeric benzyl carbinols and diastereomeric o-tolyl carbinols. The latter resulted from an unexpected benzyl to o-tolyl rearrangement. The proportion of benzyl versus o-tolyl derivatives depended on the reaction conditions. Benzylmagnesium chloride afforded predominantly o-tolyl carbinols while the application of benzylmagnesium bromide led preferably to the o-tolyl carbinols only when used in excess or at higher temperatures. The structures of the benzyl and o-tolyl derivatives were confirmed unambiguously by NMR spectral data and X-ray crystallographic analysis of their 5-ketone analogues obtained by oxidation of the corresponding mixture of diastereomeric carbinols. A possible mechanism for the Grignard reaction leading to the benzyl -> o-tolyl rearrangement is also proposed.
17.	Bialik, Marta, et al. (author) Na2CO3-Na2SO4-double salt scaling in black liquor evaporators : solubility experiments in model solutions 2017 In: International chemical recovery conference, May 24-26, 2017, Halifax, Canada. Conference paper (peer-reviewed)abstract Scaling by Na2CO3-Na2SO4-type solids counts among the most common problems in black liquor evaporation. Previous studies have identified two double salts precipitating from Na-CO3-SO4 solutions: burkeite, Na2CO3·2Na2SO4 and (sodium sulphate) dicarbonate, Na2SO4·2Na2CO3. The latter is believed to be more prone to cause scaling. However, it has long been suspected that other double salts, with largely unknown properties, may form in this system. This work summarizes the results of precipitation studies in the Na2CO3-Na2SO4-(additive) system targeting the transition zone between burkeite and dicarbonate formation. At least one additional double salt has been identified by X-ray diffraction in both bulk crystals and in the scale. The solubility data and the equilibrium liquor compositions have been compared with earlier models
18.	Borel, Cédric, 1979, et al. (author) catena-Poly[[bis(N,N'-dimethylformamide)cadmium(II)]-μ2-oxalato] 2008 In: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E64:1, s. m185- Journal article (peer-reviewed)abstract The title compound, [Cd(C2O4)(C3H7NO)2]n, is isostructural with its MnII analogue. The structure comprises zigzag polymeric chains with the oxalate groups situated on inversion centres and the CdII atoms located on twofold rotation axes.The coordination geometry around CdII is distorted octahedral and the intrachain Cd...Cd distance is 5.842(1) Å. C—H...O hydrogen bonds exist between the parallel polymeric chains.
19.	Borel, Cédric, 1979, et al. (author) Family of Isoreticular Chiral Metal-Organic Frameworks Based on Coordination and Hydrogen Bonds in [M[Co(ethylenediamine)(oxalato)2]2] 2010 In: Crystal Growth & Design. - : American Chemical Society (ACS). - 1528-7483 .- 1528-7505. ; 10:4, s. 1971-1978 Journal article (peer-reviewed)abstract From the parent compound [Ca[Co(ethylenediamine)(oxalato)2]2]n . 4H2O, 1, a series of framework compounds was prepared via the soluble sodium salt and crystal growth with the divalent metal ions Cd2+, Mn2+, and Sr2+, (2-4). These compounds have the same general formula [M[Co(ethylenediamine)(oxalato)2]2]n . xH2O, and they all form the same four- and eight-connected 3D net having scu topology (and are thus isoreticular) with water filled channels of variable size running in one direction of the crystals. However, they crystallize in two different space groups, the chiral P21) (3, 4, and the low temperature form of 1) and the noncentrosymmetric P-4 (1 and 2). The potential voids upon water removal are 18-20% of the unit cell. Preliminary gas sorption measurements at 298 K and 8 bar show substantial CO2 and N2O uptake (12-14% and 15-16% by mass, respectively), while the H2 uptake was 0.18%, a relatively high value considering the low pressure and high temperature.
20.	Borel, Cédric, 1979, et al. (author) Network analysis of barium oxalates Ba(C2O4)m(HC2O4)n(H2C2O4)p(H2O)q, including the new, uniform, five-connected loh net 2009 In: Inorganic Chemistry Communication. - : Elsevier BV. - 1387-7003. ; 12:2, s. 105-108 Journal article (peer-reviewed)abstract The structures of three compounds from the system Ba(C2O4)m(HC2O4)n(H2C2O4)p(H2O)q have been structurally reinvestigated by low-temperature X-ray diffraction. Ba(C2O4)(H2O)2, 1, Ba(C2O4)(H2C2O4)(H2O)2, 2, and Ba(C2O4)0.5(HC2O4)(H2O), 3. The compounds are composed of three-dimensional coordination network structures with bridging oxalates and water molecules. Compound 1 is binodal, four and five connected with topology (4462)(4466)-tcs; 2 contains the common 66-dia net and 3 displays the new uniform network topology 610-loh. Together with the recently reported 610-ghw and 610-rld-z nets, and the 610-fnu net, the loh net forms a subclass of five-connected 610-nets based on the distorted trigonal bipyramidal coordination.
21.	Brelid, Harald, 1960, et al. (author) Preliminary results from X-ray diffraction and EDXA studies of inorganiccomponents in softwood kraft pulp 2004 In: WURC, Wood Ultra Structure Research Centre International Seminar, Uppsala. Conference paper (other academic/artistic)
22.	Casari, Barbara, et al. (author) A redetermination of cis-aquabis(glycinato-κ2N,O)copper(II) 2004 In: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E60:12, s. m1949-m1951 Journal article (peer-reviewed)abstract The crystal structure of the title compound, [Cu(C2H4NO2)2(H2O)], reported by Freeman et al. [(1964). Acta Cryst. 17, 1463-1470], has been reinvestigated and its absolute configuration established by anomalous dispersion effects. The origin of chirality in the crystalline state of this compound is the formation of right-handed helices from a CuII coordination network self-resolved into a pure enantiomeric phase.
23.	Casari, Barbara M., et al. (author) A pseudo-merohedrally twinned rare-earth sulfate: K6[Ce(HSO4)2(SO4)4]·H2O, a novel structure type 2007 In: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C63:4, s. i25-i27 Journal article (peer-reviewed)abstract A novel structure type of an acidic rare-earth sulfate, hexapotassium cerium dihydrogensulfate tetrasulfate monohydrate, is reported. The crystal is twinned, mimicking tetragonal symmetry. The CeIV atom is nine-coordinate, connecting to one corner-sharing and four edge-sharing sulfate groups. One of the potassium ions is disordered over two general positions. The compound is unique as it contains rare-earth monomers, [Ce(HSO4)(SO4)4]5-. The structure is composed of these monomers, water molecules, discrete hydrogensulfate ions and potassium ions held together by ionic interactions. There are two types of alternating layers in the structure, with compositions [K4Ce(HSO4)(SO4)4]- and [K2(HSO4)(H2O)]+.
24.	Casari, Barbara M., et al. (author) Dipotassium tetrachromate(VI), K2Cr4O13 2005 In: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C61:12, s. i117-i119 Journal article (peer-reviewed)abstract The structure of dipotassium tetrachromium(VI) tridecaoxide, K2Cr4O13, has been determined from single-crystal X-ray data collected at 173(2)K on a racemically twinned crystal with monoclinic Pc space-group symmetry. The structure is composed of discrete [Cr4O13]2- zigzag chains held together by the charge-balancing potassium ions. The conformations adopted by the tetrachromate anion in alkali metal salts and Cr8O21 are different and can be divided into three categories.
25.	Casari, Barbara M., et al. (author) New Aquapentachlorochromate(III) Compounds: K2[CrCl5(H2O)] and (NH4)2[CrCl5(H2O)] 2006 In: Zeitschrift für Anorganische und Allgemeine Chemie. - 0044-2313 .- 1521-3749. ; 632:1, s. 101-106 Journal article (peer-reviewed)abstract Synthesis and crystal structures of two new compounds, K2[CrCl5(H2O)] (I) and (NH4)2[CrCl5(H2O)] (II) are reported. Both compounds were prepared from chromium(VI) salts by two different methods and reaction pathways of these syntheses are suggested. The crystal structures of these two aquapentachlorochromates(III) have been determined from three dimensional X-ray data collected at low temperature, 173 K. The two structures are isomorphous and their unit cell dimensions are quite similar. They are orthorhombic, space groups Pnma, with Z = 4. Both structures are composed of [CrCl5(H2O)]2- units held together by the counterion framework. The coordination around the chromium ion deviates from a regular octahedron due to the shorter equatorial chromium-oxygen bond.
26.	Casari, B. M., et al. (author) New mixed-valence chromium structure type : NH4Cr(CrO4)(2) 2006 In: Journal of Solid State Chemistry. - : Elsevier BV. - 0022-4596 .- 1095-726X. ; 179:1, s. 296-301 Journal article (peer-reviewed)abstract Synthesis and crystal structure of a new structure type of mixed Cr(III)/Cr(VI) chromates is reported. NH4Cr(CrO4)(2) was prepared from CrO3 in the presence of (NH4)(2)Ce(NO3)(6). Since this is the first preparation of mixed valence ternary chromium oxides from aqueous solution, a reaction pathway for this synthesis is suggested. The crystal structure of NH4Cr(CrO4)2 has been determined from three-dimensional X-ray data collected at low temperature, 173 K. The structure belongs to the orthorhombic space group Pnma, with a = 14.5206(10), b = 5.4826(4), c = 8.7041(7) angstrom and Z = 4. The title compound consists of corner-sharing chromium(III) octahedra and chromium(VI) tetrahedra forming a three-dimensional network with the composition [Cr(CrO4)(2]n)(n-), containing channels in which zigzag rows of ammonium ions balance the net charge.
27.	Casari, Barbara M., et al. (author) New Open-Framework Mixed-Valence Chromium(III) Cerium(III)/(IV) Sulfate: CrCeIII7CeIV6(HSO4)6(SO4)21·75H2O 2007 In: European Journal of Inorganic Chemistry. ; 2007:22, s. 3514-3518 Journal article (peer-reviewed)abstract The title compound, synthesized from CrVI and CeIV species, crystallizes in the space group P63 with a = 19.3015(2), c = 25.2684(4) Å, and Z = 2. The structural design of the title compound differs essentially from structures of known mixed-valence cerium compounds which all form three-dimensional networks. In the title compound the cerium atoms, interlinked by sulfate groups, extend to form layers held together by hydrogen-bonding contacts. Perpendicular to these layers there are 10 Å wide channels. One third of the channels host solvent water only, while the other two thirds of the channels also host [Cr(H2O)6]3+ and [Ce(SO4)3(H2O)6]3- units, blocking each of these channels once per unit cell, resulting in 14 Å long voids.
28.	Casari, Barbara M., et al. (author) New Structure Type among Octahydrated Rare-Earth Sulfates, β-Ce2(SO4)3·8H2O, and a new Ce2(SO4)3·4H2O Polymorph 2007 In: Zeitschrift für Anorganische und Allgemeine Chemie. - : Wiley. - 0044-2313 .- 1521-3749. ; 633:7, s. 1074-1081 Journal article (peer-reviewed)abstract Syntheses, crystal structures and thermal behavior of two new hydrated cerium(III) sulfates are reported, Ce2(SO4)3·4H2O (I) and β-Ce2(SO4)3·8H2O (II), both forming three-dimensional networks. Compound I crystallizes in the space group P21/n. There are two non-equivalent cerium atoms in the structure of I, one nine- and one ten-fold coordinated to oxygen atoms. The cerium polyhedra are edge sharing, forming helically propagating chains, held together by sulfate groups. The structure is compact, all the sulfate groups are edge-sharing with cerium polyhedra and one third of the oxygen atoms, belonging to sulfate groups, are in the S-Oμ3-Ce2 bonding mode. Compound II constitutes a new structure type among the octahydrated rare-earth sulfates which belongs to the space group Pn. Each cerium atom is in contact with nine oxygen atoms, these belong to four water molecules, three corner sharing and one edge sharing sulfate groups. The crystal structure is built up by layers of [Ce(H2O)4(SO4)]nn+ held together by doubly edge sharing sulfate groups. The dehydration of II is a three step process, forming Ce2(SO4)3·5H2O, Ce2(SO4)3·4H2O and Ce2(SO4)3, respectively. During the oxidative decomposition of the anhydrous form, Ce2(SO4)3, into the final product CeO2, small amount of CeO(SO4) as an intermediate species was detected.
29.	Casari, Barbara M., et al. (author) Syntheses and Crystal Structures of Hydrated Ternary Cerium Sulfates: Mixed-valence K5Ce2(SO4)6·H2O and K2Ce(SO4)3·H2O 2007 In: Zeitschrift für Anorganische und Allgemeine Chemie. - : Wiley. - 0044-2313 .- 1521-3749. ; 633:7, s. 1055-1061 Journal article (peer-reviewed)abstract A new chemical and structural interpretation of K5Ce2(SO4)6·H2O (I) and a redetermination of the structure of K2Ce(SO4)3·H2O (II) is presented. The mixed-valent compound I crystallizes in the space group C2/c with a = 17.7321(3), b = 7.0599(1), c = 19.4628(4) Å, beta = 112.373(1)° and Z = 4. Compound I has been discussed earlier with space group Cc. In the structure of I, there are pairs of edge sharing cerium polyhedra connected by sulfate oxygen atoms in the 3 bonding mode. These cerium dimers are linked through edge and corner sharing sulfate bridges, forming layers. The layers are joined by potassium ions which together with the water molecules are placed between the layers. No irregularity in the distribution of the CeIII and CeIV to cause the lost of a crystallographic center of symmetry was detected. We suggest that the charge exerted by the extra f1 electron for every cerium dimer is delocalized over the Ce1-O2-Ce2 moiety in a non-bonding mode. As a result, the oxidations state of each cerium ion is a mean value between III and IV at each atomic position. Compound II crystallizes in the space group C2 with a = 20.6149(2), b = 7.0742(1), c = 17.8570(1) Å, beta = 122.720(1)° and Z = 8. The hydrogen atoms have been located and the absolute structure has been established. Neither hydrogen atom positions nor anisotropic displacement parameters were given in the previous reports. In compound II, the cerium polyhedra are connected by edge and corner sharing sulfate groups forming a three-dimensional network. This network contains Z-shaped channels hosting the charge compensating potassium ions.
30.	Casari, Barbara M., et al. (author) Synthesis Methods for Ce(CrO4)2 · xH2O and Crystal Structures of K2CrSO7, (NH4)2Cr2O7 and Na2Cr2O7 · 2H2O 2007 In: Zeitschrift für Naturforschung - Section B Journal of Chemical Sciences. - 0932-0776. ; 62b:6, s. 771-777 Journal article (peer-reviewed)abstract New and quick methods to synthesize Ce(CrO4)2 · 2H2O and Ce(CrO4)2 · H2O, giving high yields,are described. The methods are based on exchange reactions by refluxing in water or on solid statereactions. The first crystal structure containing a chromatosulfato ion is presented. K2CrSO7 belongsto space group P21/n with a=7.4024(1), b=7.3908(1), c=12.9883(2) Å , β=90.021(1)◦ and Z = 4.The CrSO72− ion, consisting of one chromate group sharing one oxygen atom with one sulfate group, has a pseudo syn-C2v conformation with eclipsed oxygen atoms. K2CrSO7 forms a three dimensional network of CrSO72− ions held together by the charge balancing potassium ions, with the generalstructural features common with dichromate-like structures. The redetermination of the structures of(NH4)2Cr2O7 (space group C2/c, with hydrogen atoms located) and Na2Cr2O7 · 2H2O (space group P21, with hydrogen atoms located and the absolute structure established) are reported.
31.	Casari, Barbara M., et al. (author) The orthorhombic polymorph of diammonium trichromate(VI) decaoxide, α-(NH4)2Cr3O10 2007 In: Journal of Chemical Crystallography. - : Springer Science and Business Media LLC. - 1074-1542 .- 1572-8854. ; 37:2, s. 135-140 Journal article (peer-reviewed)abstract Synthesis and crystal structure of a trichromium(VI) decaoxide compound, α-(NH4)2Cr3O10, is reported. The crystal structure has been determined from three dimensional X-ray data collected at low temperature, 173 K. The structure is isomorphous with its Rb and Cs trichromate analogues, orthorhombic, space group Pbca, with a = 11.2558(3), b = 9.3193(3), c = 18.9819(5) Å and Z = 8. The title compound is composed of discrete [Cr3O10]2- chains held together by the counter ion charge and a hydrogen bonding network. The different conformations adopted by trichromate anion within its ammonium, alkali and organic salts are discussed.
32.	Casari, Barbara M., et al. (author) Two Ce(SO4)2·4H2O polymorphs: Crystal structure and thermal behavior 2007 In: Journal of Solid State Chemistry. - : Elsevier BV. - 0022-4596 .- 1095-726X. ; 180:5, s. 1616-1622 Journal article (peer-reviewed)abstract Syntheses, crystal structures and thermal behavior of two polymorphic forms of Ce(SO4)2·4H2O are reported. The first modification, α-Ce(SO4)2·4H2O (I), crystallizes in the orthorhombic space group Fddd, with a=5.6587(1), b=12.0469(2), c=26.7201(3) Å and Z=8. The second modification, β-Ce(SO4)2·4H2O (II), crystallizes in the orthorhombic space group Pnma, with a=14.6019(2), b=11.0546(2), c=5.6340(1) Å and Z=4. In both structures, the cerium atoms have eight ligands: four water molecules and four sulfate groups. The mutual position of the ligands differs in (I) and (II), resulting in geometrical isomerism. Both these structures are built up by layers of Ce(H2O)4(SO4)2 held together by a hydrogen bonding network. The dehydration of Ce(SO4)2·4H2O is a two step (I) and one step (II) process, respectively, forming Ce(SO4)2 in both cases. During the decomposition of the anhydrous form, Ce(SO4)2, into the final product CeO2, intermediate xCeO2·yCe(SO4)2 species are formed.
33.	Chen, HonQui, et al. (author) Determining the crystal symmetry of epitaxial Tl-2201 thin films by X-ray diffraction 2002 In: Physica. C, Superconductivity. - 0921-4534. ; 371:2, s. 83-89 Journal article (peer-reviewed)abstract The crystal symmetry of epitaxial Tl-2201 films on LaAlO3 and SrTiO3 substrates is investigated by X-ray diffraction. In the case of Tl1.85Ba2CuO6 film, a φ-scan of the (1 1 10) reflection showed four diffraction peaks separated by 90.00±0.02°. A 2θ-scan of the same reflection exhibited a single peak. 2Θ−ω- and φ-scans of the corresponding reflection in Tl2.04Ba2CuO6 show splitting and broadening of the diffraction peaks indicating an orthorhombic distortion. The effect of errors in film alignment on the φ-scan and 2Θ−ω-scans is discussed. A periodic function, δ=a+bsin(ω−φ), was used to correct the φ-scan measurements. The influence of lattice mismatch between film and substrate on the structural symmetry of the films is discussed.
34.	Dey, Raja, 1963, et al. (author) 21-Deoxycortisone (17α-hydroxy-4-pregnene-3,11,20-trione) 2005 In: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C61:4, s. o201-o203 Journal article (peer-reviewed)abstract The title compound, C21H28O4, a synthetic glucocorticoid, crystallizes with a single molecule in the asymmetric unit. Ring A is almost in a half-chair conformation, rings B and C are almost in chair conformations, and ring D is between a twist and a 13β-envelope conformation. The A/B ring junction is quasi-trans, whereas the B/C and C/D ring junctions both approach trans characteristics. The molecule as a whole is slightly convex towards the β side, with an angle of 9.60(2)° between the C10-C19 and C13-C18 vectors. Molecular-packing and hydrogen-bonding (both intra- and intermolecular) interactions play a major role in the structural association of the compound.
35.	Dey, Raja, 1963, et al. (author) 5-Amino-1-[2-(diethylamino)ethyl]-1H-imidazole-4-carboxamide 2006 In: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E62:2, s. o814-o816 Journal article (peer-reviewed)abstract Intramolecular hydrogen bonds influence the molecular conformation of the title compound, C10H19N5O, resulting in an extended planar hydrogen-bonded heterocyclic ring structure. The bulky diethylaminoethyl group adopts a butterfly conformation. The stabilization of the crystal structure is supported by an extensive network of intermolecular hydrogen bonds.
36.	Dey, Raja, 1963, et al. (author) 5-Amino-1-benzyl-4-cyano-3-methylimidazolium toluene-p-sulfonate 2005 In: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E61:12, s. o4039-o4041 Journal article (peer-reviewed)abstract The title compound, C12H13N4+·C7H7O3S-, contains an imidazolium cation and a toluene-p-sulfonate anion in the asymmetric unit. Hydrogen-bonded dimers are formed between the cyano and amino groups of inversion-related imidazolium cations.
37.	Dey, Raja, 1963, et al. (author) A titanium salicylate, Na4[Ti(C7H4O3)3]2·11H2O 2005 In: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E61:8, s. m1495-m1497 Journal article (peer-reviewed)abstract The title compound, tetrasodium bis[tris(salicylatotitanate(IV)] undecahydrate, Na4[Ti(C7H4O3)3]2·11H2O, crystallizes with two titanium salicylate complex ions, four sodium ions and 11 water molecules in the asymmetric unit. One water O atom is disordered over two positions, having 0.74(5) and 0.26(5) occupancy. Both Ti atoms and three sodium ions adopt a distorted octahedral coordination by O atoms. The fourth sodium ion has a distorted trigonal-bipyramidal coordination by oxygen, sharing one edge with a sodium coordination octahedron.
38.	Diaz, Jesus Garcia, et al. (author) Bis(cyanamidonitrato-κN)[tris(3,5-dimethylpyrazole)copper(II) 2003 In: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E59:5, s. m241-m243 Journal article (peer-reviewed)abstract The title compound, [Cu(CN3O2)2(C5H8N2)3], is the first example of a pentacoordinated 3d-central atom involving the cyanamidonitrate ligand. The crystal structure is formed by neutral molecues stabilized by a three-dimensional network consisting of one intramolecular and three intermolecular hydrogen bonds. The Cu atom is pentacoordinated by three N-donor atoms from 3,5-dimethylpyrazole neutral ligands and two N-donor atoms from cyanamidonitrate anions.
39.	Diaz, Jesus Garcia, et al. (author) Pseudo-merohedrally twinned tetrakis(1H-imidazole-κN3)bis(N-nitrocyanamidato-κN)copper(II) 2005 In: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C61:4, s. m180-m182 Journal article (peer-reviewed)abstract Crystals of the title complex, [Cu(CN3O2)2(C3H4N2)4], the structure of which has been determined by single-crystal X-ray diffraction at 304 K, appear to be pseudo-merohedrally twinned. Transformation to a monoclinic C-centred cell was necessary in order to derive the twin law. Twin refinement in a triclinic unit cell significantly reduced the R value. The asymmetric unit of the triclinic cell consists of one molecule in a general position and two half entities with the Cu atom on a centre of inversion. The coordination of the Cu atom is quasi-octahedral, with four imidazole N-atom donors in the equatorial plane and two cyano N atoms from the N-nitrocyanamidate anion in axial positions. Owing to symmetry in the centrosymmetric molecules, the trans imidazole ligands are parallel, while those in the non-centrosymmetric molecule make angles of 22.8(2) and 77.9(2)°.
40.	El Massry, Abdel Moneim, et al. (author) Synthesis and structure elucidation of novel fused 1,2,4-triazine derivatives as potent inhibitors targeting CYP1A1 activity 2012 In: Bioorganic and Medicinal Chemistry. - : Elsevier BV. - 0968-0896 .- 1464-3391. ; 20:8, s. 2624-2637 Journal article (peer-reviewed)abstract Synthesis and structure elucidation of new series of novel fused 1,2,4-triazine derivatives 3a-3f, 4a-4i and 6a-6b and their inhibitory activities are presented. Molecular structures of the synthesized compounds were confirmed by H-1 NMR, C-13 NMR, MS spectra and elemental analyses. X-ray crystallographic analysis was performed on 2-acetyl-8-(N,N-diacetylamino)-6-(4-methoxybenzyl)-3-(4-methoxy-phenyl)- 7-oxo-2,3-dihydro-7H-[1,2,4]triazolo[4,3-b][1,2,4]triazine 3d and 2-acetyl-8-(N-acetyl- amino)-6-benzyl-3-(4-chlorophenyl)-3-methyl-7-oxo-2,3-dihydro-7H-[1,2,4] triazolo[4,3-b][1,2,4]triazine 4e to secure their structures. The inhibitory effect of these compounds toward the CPY1A1 activity was screened to determine their potential as promising anticancer drugs. Our data showed that compounds 4e, 5a, 5b and 6b possess the highest inhibitory effects among all tested compounds. Furthermore, analysis of triazolotriazine derivatives docking showed that these compounds bind only at the interface of substrate recognition site 2 (SRS2) and (SRS6) at the outer surface of the protein. Amino-acids ASN214, SER216 and ILE462 participate in the binding of these compounds through H-bonds.
41.	Erdélyi, Máté, et al. (author) Insight into beta-hairpin stability : a structural and thermodynamic study of diastereomeric beta-hairpin mimetics 2002 In: New Journal of Chemistry. - 1144-0546 .- 1369-9261. ; 26, s. 834-843:26, s. 834- Journal article (peer-reviewed)abstract Two diastereomers of a model β-hairpin peptide mimetic were synthesized and studied with a combination of experimental (NMR, X-ray, CD, MS, IR) and computational methods (Monte Carlo/molecular mechanics calculations). The secondary structure-stabilizing eﬀects of hydrophobic interactions and hydrogen bonding were investigated. Comparison of the extent of folded hairpin population in non-competitive, polar aprotic, and polar protic solvents illustrates the critical role of intramolecular hydrogen bonding on hairpin stability. Investigation of 1H NMR melting curves of the diastereomeric compounds in a variety of solvents allowed an evaluation of the role of hydrophobic eﬀects on secondary structure stabilization to be made.
42.	Erdelyi, Mate, 1975, et al. (author) Insight into β -hairpin stability: a structural and thermodynamic study of diastereomeric β-hairpin mimetics 2002 In: New Journal of Chemistry. - 1369-9261 .- 1144-0546. ; 26, s. 834-843 Journal article (peer-reviewed)abstract Two diastereomers of a model β-hairpin peptide mimetic were synthesized and studied with a combination of experimental (NMR, X-ray, CD, MS, IR) and computational methods (Monte Carlo/molecular mechanics calculations). The secondary structure-stabilizing effects of hydrophobic interactions and hydrogen bonding were investigated. Comparison of the extent of folded hairpin population in non-competitive, polar aprotic, and polar protic solvents illustrates the critical role of intramolecular hydrogen bonding on hairpin stability. Investigation of 1H NMR melting curves of the diastereomeric compounds in a variety of solvents allowed an evaluation of the role of hydrophobic effects on secondary structure stabilization to be made.
43.	Eriksson, Annika, et al. (author) Dirubidium aquapentachlorochromate(III) and dicaesium aquapentachlorochromate(III) 2004 In: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C60:4, s. i40-i42 Journal article (peer-reviewed)abstract The structures of the two novel title compounds, Rb2[CrCl5(H2O)], (I), and Cs2[CrCl5(H2O)], (II), have been determined by single-crystal X-ray diffraction. Compounds (I) and (II) crystallize with Pnma and Cmcm symmetry, respectively. In (I), the Cr, three Cl and water O atom lie on a mirror plane; in (II), the Cs, Cr, O and one of the Cl atoms are at sites with m2m symmetry. The chromate anions are in a pseudo-cubic environment of eight Rb+ cations in (I) and in a pseudo-octahedral environment of six Cs+ cations in (II). The structural arrangement correlates with the r(anion)/r(cation) radius ratio.
44.	Eriksson, Annika, 1975, et al. (author) Pentapotassium sodium hexasulfatodicerate(III) 2003 In: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E59:11, s. i149-i150 Journal article (peer-reviewed)abstract K5Na[Ce2(SO4)6] contains two CeIII ions, cross-linked via two oxygen and four sulfate bridges, a unique configuration for cerium sulfates. Each cerium is (8 + 2)-coordinated by O atoms of four sulfate groups by bidentate linkages.
45.	Eriksson, Annika, et al. (author) Tetramethylammonium tetraaquadichlorochromium(III) trichloride dihydrate 2004 In: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E60:7, s. m930-m932 Journal article (peer-reviewed)abstract The title metal-organic octahedral chromium compound, (C4H12N)2[CrCl2(H2O)4]Cl3·2H2O, was synthesized according to the Palmer method. The chromium complex ion possesses mirror symmetry and has two axial Cl- ions and four equatorial water molecules. The octahedral complex cation and tetramethyl ammonium tetrahedra pack in a 'parquet'-style pattern, with Cl- ions and water molecules in between the 'bricks'. The structure is compared with aquapentachlorochromate(III) complexes in the literature.
46.	Fogel, Nina Ya. 1938, et al. (author) Interfacial superconductivity in semiconducting monochalcogenide superlattices 2002 In: Physical Review B - Condensed Matter and Materials Physics. - 2469-9950 .- 2469-9969. ; 66:17, s. 174513(11pp.)- Journal article (peer-reviewed)abstract Superconducting and structural properties of superconducting semiconducting multilayers are investigated. These layered systems are obtained by epitaxial growth of the isomorphic monochalcogenides of Pb, Sn, and rare-earth elements on a KCl substrate. Some of these compounds are narrow-gap semiconductors (PbTe, PbS, PbSe, SnTe). Layered structures containing one or two narrow-gap semiconductors have a metallic type of conductivity and a transition to a superconducting state at temperatures in the range of 2.56 K. Structures containing only wide-gap semiconductors (YbS, EuS, EuSe) do not demonstrate such properties. All superconducting layered systems are type-II superconductors. The critical magnetic fields and the resistive behavior in the mixed state reveal features characteristic of other layered superconductors. However, data obtained in magnetic fields testify that the period of the superstructure corresponds to half of that obtained from x-ray-diffractometry investigations. This is evidence that the superconducting layers in these samples are confined to the interfaces between two semiconductors. Electron microscopy studies reveal that in the case of epitaxial growth the interfaces contain regular grids of misfit dislocations covering all the interface area. These samples appear to undergo a superconducting transition if they have a metallic type of conductivity in the normal state. Samples with island-type dislocation grids only reveal partial superconducting transitions. The correlations between the appearance of superconductivity and the presence of dislocations, which have been found experimentally, lead to the conclusion that the normal metallic conductivity as well as the superconductivity are induced by the elastic deformation fields created by the misfit dislocation grids. A theoretical model is proposed for the description of the narrow-gap semiconductor metallization, which is due to a band inversion effect and the appearance of electron- or hole-type inversion layers near the interfaces. For different combinations of the semiconductors, such inversion layers in the superlattices can have different shapes and topology. In particular, they can form multiply connected periodic nets having a repetition period coinciding with that of the dislocation grids. Numerical estimates show that such a scenario for the appearance of superconductivity is quite likely. It is shown that the new type of metallic and superconducting nanoscale two-dimensional structures with unusual properties may be obtained from monochalcogenide semiconductors.
47.	Gharagozlou, Mehrnaz, et al. (author) Hexaaquazinc(II) bis[tris(3-carboxypyridine-2-carboxylato)zincate(II)] 2010 In: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E66:12, s. m1606-m1607 Journal article (peer-reviewed)abstract The title compound, [Zn(H2O)6][Zn(C7H4NO4)3]2, consists of two [Zn(py-2,3-dcH)3]- anions (py-2,3-dcH is 3-carboxypyridine-2-carboxylate) and one [Zn(H2O)6]2+ cation. The anion is a six-coordinate complex located on a threefold rotation axis with a slightly distorted octahedral geometry around Zn2+ ion. The cation is also six-coordinate with an octahedral geometry around the Zn atom, located at a inverse threefold axis. Non-covalent interactions such as π-π stacking [centroid-centroid distance = 3.828(4)Å] and O-H...O hydrogen bonds play important roles in stabilizing the supramolecular structure.
48.	Ghazzali, Mohamed I D M, 1974, et al. (author) 4,4'-(Azinodimethylene)dipyridinium bis(tetrafluoroborate) and 4-[(4-pyridylmethylene)hydrazonomethyl]pyridinium perchlorate: two different hydrogen-bonding motifs 2007 In: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C63:5, s. o312-o314 Journal article (peer-reviewed)abstract In the crystal structures of the title compounds, C12H12N42+·2BF4-, (I), and C12H11N4+·ClO4-, (II), respectively, infinite two- and one-dimensional architectures are built up via N-H...F [in (I)] and conventional N-H...N [in (II)] hydrogen bonding. The N-N single bond in (I) lies on a crystallographic centre of symmetry; as a result, the two pyridinium rings are parallel. In (II), the pyridinium and pyridyl ring planes are inclined with a dihedral angle of 14.45(3)°.
49.	Ghazzali, Mohamed I D M, 1974, et al. (author) A three-dimensional net of Δ-tris(1,10-phenanthroline)ruthenium(II) in the dual-metal self-assembly of bis[tris(1,10-phenanthroline)ruthenium(II)] tetraisothiocyanatoiron(II) bis(perchlorate) 2008 In: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C64:7, s. m243-m245 Journal article (peer-reviewed)abstract The title compound, [Ru(C12H8N2)3]2[Fe(NCS)4](ClO4)2, crystallizes in a tetragonal chiral space group (P41212) and the assigned absolute configuration of the optically active molecules was unequivocally confirmed. The Δ-[RuII(phen)3]2+ complex cations (phen is 1,10-phenanthroline) interact along the 41 screw axis parallel to the c axis, with an Ru...Ru distance of 10.4170(6) Å, and in the ab plane, with Ru...Ru distances of 10.0920(6) and 10.0938(6) Å, defining a primitive cubic lattice. The Fe atom is situated on the twofold axis diagonal in the ab plane. The supramolecular architecture is supported by C-H...O interactions between the [RuII(phen)3]2+ cation and the disordered perchlorate anion. This study adds to the relatively scarce knowledge about intermolecular interactions between [RuII(phen)3]2+ ions in the solid state, knowledge that eventually may also lead to a better understanding of the solution state interactions of this species; these are of immense interest because of the photochemical properties of these ions and their interactions with DNA.
50.	Ghazzali, Mohamed I D M, 1974, et al. (author) catena-Poly[[chloro(pyridinium-3-carboxylato-κO)zinc(II)]-μ-nicotinato-κ2O:N] 2007 In: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E63:1, s. m114-m116 Journal article (peer-reviewed)abstract The title bis-nicotinate zinc chloride, [Zn(C6H4NO2)Cl(C6H5NO2)]n, has an infinite head-to-tail one-dimensional chain structure. The compound was synthesized under mild hydrothermal conditions. The ZnII atom exhibits a distorted tetrahedral coordination geometry. The structure is statistically disordered, with 0.5 site occupancy for the Zn atom and the H atom located on the pyridine N atom. As a result, Zn positions in the crystal structure alternate between two sites related by a crystallographic twofold axis and rows of molecules are formed, supported by strong N-H...O hydrogen bonds.

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