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1Author    C. Friebel, V. Propach, D. ReinenRequires cookie*
 Title    in Mischkristallen BaXu^Zn^yFg Cu 2+ in Tetragonally Compressed Octahedral Coordination - Spectroscopic Investigations of Mixed Crystals Ba2Cii^.Zn1_xF6  
 Abstract    Usually the Jahn-Teller effect of Cu 2+ in a regular octahedral host lattice site leads to a tetragonal elongation with a small o-rhombic component. If the relevant crystallographic site is slightly tetragonally compressed however in the host lattice structure already — as in Ba 2 ZnF6 -the Jahn-Teller effect may stabilize this distortion symmetry as well. This can be deduced from the EPR-spectroscopic g M -values of 1.99 for the mixed crystals Ba^Zni.^Cu^Fg up to x = 0.3. The angular overlap parameters obtained from the ligand field spectra suggest in addition, that the tetragonal compression of the CuFß polyliedra is considerable, with CuF distances of about 1.90 A (2x) and 2.14 A (4x), respectively. Increasing cooperative elastic interactions between the CuFß polyhedia in the (001) planes at larger Cu 2+ -concentrations induce tetragonally elongated octahedra (with a small o-rhombic component) in antiferrodistortive order at x > 0.6. This cooperative Jahn-Teller order, which is characteristic for Ba2CuF6, can be verified simply by acentric displacements of the F~-ligands connecting two Cu 2+ -ions in the (001) planes. 
  Reference    (Z. Naturforsch. 31b, 1574—1584 [1976]; eingegangen am 13. August 1976) 
  Published    1976 
  Keywords    Jahn-Teller Effect, EPR Spectra, Ligand Field Spectra, Copper 
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 TEI-XML for    default:Reihe_B/31/ZNB-1976-31b-1574.pdf 
 Identifier    ZNB-1976-31b-1574 
 Volume    31 
2Author    Vicente Fernández, Moisés Morán, JuanCarlos Doadrio, Elke Conradi, Wolfgang Willing, Ulrich MüllerRequires cookie*
 Title    EPR-Spektren von Tetrachlorocupraten verschiedener Aminothiazoliumderivate. Die Kristallstrukturen von 2-Amino-2-thiazolinium-und 2-Amino-4-methylthiazoliumtetrachlorocuprat(II) EPR Spectra of Tetrachlorocuprates of Several Aminothiazolium Derivatives. The Crystal Structures of 2-Amino-2-thiazolinium and 2-Amino-4-methylthiazolium Tetrachlorocuprate(II)  
 Abstract    The tetrachlorocuprates. of the 2-aminothiazolium ion and of four of its substitution products, of 2-aminothiazolinium, and of 2-amino-4-carboxyl-thiazolidinium ions were prepared from the cor-responding heterocyclic bases, hydrochloric acid and copper(II) chloride in ethanol. The thermo-chromic compounds were characterized by their IR and electronic spectra. The EPR spectra of solutions, frozen solutions, and of the solids show the CUC14 2 ~ ion to have the structure of a flattened tetrahedron; in the case of some of the solids, distortions from D 2 d symmetry are observed. This was confirmed by two X-ray crystal structure determinations. Crystal data: 2-amino-2-thiazolinium tetrachlorocuprate, monoclinic, space group C2/c, a = 2772.8, b = 780.0, c = 1560.0 pm, ß = 112.04°, Z = 8 (R = 0.047 for 2527 observed, independent reflexions); 2-amino-4-methylthiazolium tetrachlorocuprate, triclinic. PI, a = 780.4, b = 853.4, c — 1381.4 pm, a = 103.50, ß = 99.39, y = 104.17°, Z = 2 (R = 0.041 for 3319 reflexions). In both compounds the flattened CuCl 4 2 " tetrahedron is distorted and has two bond angles in the range between 130 and 141°. The heterocyclic cations are protonated at their ring N atoms; the corresponding H atoms and the H atoms of the amino groups are involved in N — H--C1 hydrogen bonding. 
  Reference    (Z. Naturforsch. 42b, 15—22 [1987]; eingegangen am 31. Juli 1986) 
  Published    1987 
  Keywords    Aminothiazolium Derivates, Tetrachloro Cuprates, EPR Spectra, Crystal Structure 
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 TEI-XML for    default:Reihe_B/42/ZNB-1987-42b-0015.pdf 
 Identifier    ZNB-1987-42b-0015 
 Volume    42 
3Author    Reiner Figge, Claus Friebel, U. Te Patt-Siebel, Ulrich Müller, Kurt DehnickeRequires cookie*
 Title    Nitridokomplexe von Molybdän(V); Synthesen, IR-und EPR-Spektren. Die Kristallstruktur von [Na(15-Krone-5)Na(THF)]2[MoNCI3 THF]4-2THF Nitrido Complexes of M olybdenum (V ); Syntheses, IR , and EPR Spectra. Crystal Structure of [N a(15-Crow n-5)N a(TH F)]2[MoNCl3-THF]4-2T H F  
 Abstract    Nitrido C om plexes o f M olyb denu m (V), 
  Reference    Z. Naturforsch. 44b, 1377—1384 (1989); eingegangen am 30. Mai 1989 
  Published    1989 
  Keywords    Syntheses, IR Spectra, EPR Spectra, Crystal Structure 
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 TEI-XML for    default:Reihe_B/44/ZNB-1989-44b-1377.pdf 
 Identifier    ZNB-1989-44b-1377 
 Volume    44 
4Author    Einar Möller, Joachim Sieler, Reinhard KirmseRequires cookie*
 Title    Synthese, Struktur-und EPR-Untersuchungen an 57Fe-markiertem Tetra- w-butylammonium-bis(l,l-dicyanoethen-2,2-dithiolato)nitrosyleisen(I), («-Bu4N)2 [57Fe(NO)(/-mnt)2] Synthesis, Structural, and EPR Investigations on 57Fe Enriched Tetra-n-butylammonium- bis(l,l-dicyanoethene-2,2-dithiolato)nitrosyliron(I), («-Bu4N )2[57Fe(NO)(/-mnt)2]  
 Abstract    The molecular structure and X-as well as Q-band EPR studies of tetra-«-butylammonium-bis(l,l-dicyanoethene-2,2-dithiolato)nitrosyliron(I) enriched with 57Fe are reported, (n-Bu4N)2[Fe(NO)(/-mnt)2] crystallizes triclinically, space group P i with a = 9,5147(7) A, b = 10,4841(8) A, c = 25,840(2) A, a = 92,510(1)°, ß = 92,895(1)°, 7 = 1 1 1 ,1 5 6 (1)° , Z = 2. The g and the hyperfine coupling tensors AN and AFe derived from the EPR spectra are rhombically-symmetric: g, = 2,043, g~> = 2 039, g3 = 2,031, A ,N = 13 ,8 1 0 ~ 4cm _ l , Ai N = 1 l ,6 1 0 _4cm _lI A3N = 15,2-10_4cm _T, A ,Fe = ll,4 -1 0 ~ 4cm _ l , A2Fe = 1 5 ,7 1 0 '4c m " r and A 3Fe = -2,6-10_4cm _1. The spin-density distribution within the first coordination sphere is discussed. 
  Reference    Z. Naturforsch. 52b, 919—926 (1997); eingegangen am 1. April 1997 
  Published    1997 
  Keywords    Nitrosyliron(I) Complexes, Crystal Structure, EPR Spectra 
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 TEI-XML for    default:Reihe_B/52/ZNB-1997-52b-0919.pdf 
 Identifier    ZNB-1997-52b-0919 
 Volume    52 
5Author    HeinzP. Fritz, Peter DavidRequires cookie*
 Title    Alkali-Polyketenenolat, ein Polyacetylen-Derivat Alkali-Polyketene-Enolate, a Polyacetylene Derivative  
 Abstract    An alkali-polyketene-enolate was made from polyketene by using aqueous bases MOH (M = Li, Na, K, Rb, Cs). The structure is proposed on the basis of IR and 13 C NMR spectra, the paramagnetic properties were investigated by EPR spectroscopy. AC conductivity measurements show a maximum conductivity of 1CT 2 Sern -1 (at 115 °C), where marked ionic participation is expected. Doping of the polyacetylene backbone with iodine gives no increase of conductivity; CV measurements indicate the presence of triiodide anions. 
  Reference    Z. Naturforsch. 43b, 671—676 (1988); eingegangen am 8. November 1987 
  Published    1988 
  Keywords    Alkali-Polyketene-Enolate, Polyketene, 13 C NMR Spectra, EPR Spectra, Conductivity 
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 TEI-XML for    default:Reihe_B/43/ZNB-1988-43b-0671.pdf 
 Identifier    ZNB-1988-43b-0671 
 Volume    43 
6Author    Gabriela Stănciuca, MironT C Ăproiua, Horia Căldărarub, Agneta Caragheorgheopolb, Titus Constantinescub, A. Lexandru, T. B. AlabancRequires cookie*
 Title    Factors Affecting Stability and Equilibria of Free Radicals, XVII+ EPR Evidence for Formation of N-AIkoxypicramides on Oxidation of N-Alkoxy-dinitroanilines. Electronic Structure of Aminyl Radicals  
 Abstract    Oxidation of N-alkoxy-2,6-or -2,4-dinitroanilines with various oxidizing agents yields the corre­ sponding N-alkoxydinitrophenyl-am inyls, which then undergo spontaneous conversion into the corresponding N-alkoxy-2.4.6-trinitrophenyl-am inyls. The EPR spectra o f all these persistent aminyls are presented and discussed. Such disproportionations did not occur in capto-dative diaryl-aminyls which had lower spin densities on the electron-acceptor group than the present N-alkoxy-polynitrophenyl-am inyls (these have, in addition, N —O bonds which are less strong than N —C bonds). Electronic structures o f diaryl-aminyls and N-alkoxy-aryl-aminyls are discussed: both are ;r-radicals, but they probably possess at the nitrogen atom an approximately linear, and a kinked structure, respectively. 
  Reference    Z. Naturforsch. 44b, 1459 (1989); received June 26 1989 
  Published    1989 
  Keywords    Capto-dative Am inyls, EPR Spectra, D isproportionation, jr-Radicals 
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 TEI-XML for    default:Reihe_B/44/ZNB-1989-44b-1459.pdf 
 Identifier    ZNB-1989-44b-1459 
 Volume    44 
7Author    (. N., G. Cl, U. Steffen3, M.A H Kaschuba3, D. Itchm Anb, Reinen3Requires cookie*
 Title    Über die Natur der Cu2+-Zentren im N H 4C1 - die spektroskopische Untersuchung von Cu2+-dotiertem H g(N H 3)2Cl2 The N ature of the Cu2+ Centres in N H 4C1 - a Spectroscopic Investigation of Cu2+ Doped  
 Abstract    The preparation o f H g(N H 3)2Cl2 doped with a small amount o f Cu2+ is reported. The EPR and ligand field reflectance spectra indicate the presence o f "CuC14(N H 3)2" polyhedra with a compressed tetragonal geometry and confirm, that the centres in Cu2+ doped N H 4C1 possess the same geometry -as postulated earlier. The Cu2+ centres in H g(N H 3),C l2 are less com ­ pressed than those in N H 4C1, however, as could be deduced from the copper(II) hyperfine values, which are strongly influenced by the quite different admixture o f the metal 4 s orbital into the A lg (d,?) ground state in the two cases, and from the comparable energies o f the d -d transitions. 
  Reference    Z. Naturforsch. 47b, 465 (1992); eingegangen am 12. September 1991 
  Published    1992 
  Keywords    Compressed CunCl4(N H 3)2 Centres, Vibronic Jahn-Teller Coupling, EPR Spectra 
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 TEI-XML for    default:Reihe_B/47/ZNB-1992-47b-0465.pdf 
 Identifier    ZNB-1992-47b-0465 
 Volume    47 
8Author    Somluck Ruangsuttinarupap, Claus Friebel, Kurt DehnickeRequires cookie*
 Title    Synthese, IR-, EPR-und Elektronenspektren der Dischwefel-dinitrid-Komplexe [CUC1 2 (CH 3 CN)] 2 -(/I-S 2 N 2 ) und [CuCl 2 ] 2 * (/I-S 2 N 2 ) Synthesis, IR, EPR, and Electronic Spectra of the Disulfur Dinitride Complexes [CUC1 2 (CH 3 CN)] 2 * (w-S 2 N 2 ) and [CuCl 2 ] 2 -(w-S 2 N 2 )  
 Abstract    [CuCl 2 (CH 3 CN)] 2 -(W-S 2 N 2) is prepared by the reaction of trithiazyl chloride with CuCl in acetonitrile solution. Thermolysis at 120 °C yields [CuCl 2 ] 2 -(W-S 2 N 2). The complexes are charac-terized by their IR, EPR, and electronic spectra. 
  Reference    Z. Naturforsch. 42b, 337—340 (1987); eingegangen am 24. November 1986 
  Published    1987 
  Keywords    Disulfur Dinitride Complexes of Copper(II), EPR Spectra, Electronic Spectra, Synthesis, IR Spectra 
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 TEI-XML for    default:Reihe_B/42/ZNB-1987-42b-0337.pdf 
 Identifier    ZNB-1987-42b-0337 
 Volume    42 
9Author    AndreasF. Stange, Eberhard Waldhör, Michael Moscherosch, Wolfgang KaimRequires cookie*
 Title    Variable Structure of the Cu2S2 Core in Doubly Thiolate-Bridged Dicopper(I) Complexes. An X-Ray Crystallographic, Electrochemical and EPR Study of (dmp)2 (o-CH3 C6H4S)2Cu2 , dmp = 2,9-Dimethyl-l,10-phenanthroline, and a Comment on the Nature of Phenanthroline-Containing "Cu(0)" Complexes  
 Abstract    The molecular and crystal structure of the dicopper(I) complex (dm p)2(M-o-CH3C6H4S)2Cu2 (1), dmp = 2,9-dim ethyl-l,10-phenanthroline, has been deter­ mined. With Cu/S/Cu and S/Cu/S bond angles between 80 and 100°, the planar structure of the central CuSCuS four-membered ring is much more symmetric for 1 as compared to the analogous complex 2 of unsubstituted 1,10-phenanthroline which has a folded Cu2S2 core with bond angles between 67 and 108°. This result illustrates a considerable structural flexi­ bility of the LCu(m-SR)2CuL entity which is being discussed as a possible model for CuA centers of cytochrome c oxidase or nitrous oxide reductase. Oxidation of both com plexes 1 and 2 remains irreversible even at cyclovoltammetric scan rates o f 1 V/s. However, the methyl substitution in complex 1 causes increased reversibility of the electronically coupled dmp-based reduction processes. Accordingly, the EPR spectrum of l -* is characterized by hyper-fine splitting from dmp--and a relatively small 63 " Cu coupling of 0.53 mT. The stabilization of 2,9-disubstituted 1,10-phenanthroline radical anions by coordination to Cu(I) is also dem ­ onstrated by detection of a single broad EPR line at g 2.0028 for the formal "C u(0)" complex Cu(dpp)2 = CuI(dpp_-)(dpp), dpp = 2,9-diphenyl-l,10-phenanthroline. While the EPR signal of Cu(dpp)2 loses intensity on cooling, possibly due to dimerization and spin-pairing, the distorted tetrahedral configuration with essential orthogonal arrangement of dpp jz systems seem s to disfavour an intramolecular electron hopping. 
  Reference    (Z. Naturforsch. 50b, 115—122 [1995]; received July 25 1994) 
  Published    1995 
  Keywords    Crystal Structure, Copper Complexes, Sulfur Ligands, 1, 10-Phenanthrolines, EPR Spectra 
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 TEI-XML for    default:Reihe_B/50/ZNB-1995-50b-0115.pdf 
 Identifier    ZNB-1995-50b-0115 
 Volume    50