Go toArchive
Browse byFacets
Bookbag ( 0 )
'copper' in keywords Facet   Publication Year 1999  [X]
Results  3 Items
Sorted by   
Publication Year
1Author    Henri Brunner1, ManfredM. Uschiol3, Thomas Neuhierl3, Bernhard NuberbRequires cookie*
 Title    Copper Complexes with the Ligand [Cp2MoH2]  
 Abstract    The reaction of CuCl with [CP2M0H2] yields the complex [Cu(Cp2M oH2)2Cl]. An X-ray structure analysis shows that the coordination of the copper(I) ion by two [CP2M0H2] lig­ ands and the chloride ion is pseudo-trigonal planar. The hydride ligands were located by using difference Fourier methods. A manifold of reactions took place when an aqueous so­ lution of CUSO4 was treated with a solution of [Cp2M oH 2] in dichloromethane in a 1:2 molar ratio. The X-ray structure analysis established a polymeric structure of the complex [Cu(Cp2MoH2)2Cu(Cp2M oH2)S0 4 ]" with two different copper centers. 
  Reference    Z. Naturforsch. 54b, 337—340 (1999); received September 25 1998 
  Published    1999 
  Keywords    Copper, Molybdenum, X-Ray Data 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/54/ZNB-1999-54b-0337.pdf 
 Identifier    ZNB-1999-54b-0337 
 Volume    54 
2Author    Isabel Díaza, Vicente Fernández3, VitalyK. Belskyb, Jose Luis, M. Artínez0Requires cookie*
 Title    Synthesis and Structural Study of the Thermochromic Compounds Bis(2-amino-4-oxo-6-methylpyrimidinium) Tetrachlorocuprate(II) and Bis(2-amino-4-chloro-6-methylpyrimidinium) Hexachlorodicuprate(II)  
 Abstract    The compound bis(2-am ino-4-oxo-6-methylpyrimidinium) tetrachlorocuprate(II) 1 contains CuCU2-square-planar anions, and bis(2-am ino-4-chloro-6-m ethylpyrim idinium) hexachlorod-icuprate(II) 2 quasi-planar CU2CI62-anions. Both compounds show thermochromic behaviour. This phenomenon has been studied by X-ray crystallography at variable temperature, with the result that no major change is observed in the geometry o f the copper atom. Thus it is possible to assume som e influence o f the hydrogen bonds and o f the different geometries o f interme­ diate states on the color o f the compounds due to the modifications provoked in the L —>M charge transfer and in the energy o f the metal d-d transitions. Magnetic measurements o f the compounds give information on magneto-structural correlations. Compound 1 is ferromagnetic (Tc = 20 K) due to the perpendicular arrangement o f the square anions that allows exchange pathways only via Cu-Cl -Cu , H-bonding or cationic n electron interactions. Compound 2 shows a very complicated behavior at low temperature with local antiferromagnetic fluctua­ tions. Crystal data: 1 CioHioNftC^CUCu, triclinic, P i; 393(2) K: a = 11.053(2), b = 11.334(2), c = 14.038(3) (Ä), a = 95.76(3), ß = 101.35(3), 7 = 9 0 .1 5 (3) 0 ; 293(2) K: a = 11.022(2), b = 11.289(2), c = 14.001(3) (A), a = 95.86(2), ß = 101.34(2), 7 = 9 0 .0 9 (3) 0 ; 155(2) K: a = 11.008(2), b = 11.231 (2), c = 13.967(3) (A), a = 95.86(2), ß = 101.37(2), 7 = 8 9 .9 9 (2) 0 ; Z = 4. 2 (C5H7N 3C l3Cu)2, monoclinic, P 2,/c; 293(2) K: a = 5.998(1), b =18.669(4), c = 9.466(2) (A), ß = 1 0 0 .9 3 (3)0 ; 150(2) K: a = 5.971(1), b = 18.655(4), c = 9.3 8 3 (2) (Ä), ß = 1 0 1 .6 4 (1) 0 ; Z = 4. 
  Reference    Z. Naturforsch. 54b, 718 (1999); received March 1 1999 
  Published    1999 
  Keywords    Thermochromic Compounds, Copper, Chloride 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/54/ZNB-1999-54b-0718.pdf 
 Identifier    ZNB-1999-54b-0718 
 Volume    54 
3Author    M. Ciscato3 ', J. Vangronsveldb, R. Valcke3Requires cookie*
 Title    Effects of Heavy Metals on the Fast Chlorophyll Fluorescence Induction Kinetics of Photosystem II: a Comparative Study  
 Abstract    The effects of toxic concentrations of Cu, Zn and Cd on the fast induction kinetics of fluorescence from photosystem(PS)II were investigated in a comparative way. The fast fluo­ rescence transient from primary leaves of m etal-treated bean plants was studied. During several days after metal application, the time course of the changes induced by the different metals was monitored. The results evidenced not only a different time course of the changes in fluorescence related parameters for the three metals, but also different effects on the fluorescence induction kinetics, which could possibly be linked to different mechanisms of action of the metals. 
  Reference    Z. Naturforsch. 54c, 735 (1999); received November 8 1998/M arch 10 1999 
  Published    1999 
  Keywords    Cadmium, Chlorophyll Fluorescence, Copper, Heavy Metals, Zinc 
  Similar Items    Find
 TEI-XML for    default:Reihe_C/54/ZNC-1999-54c-0735.pdf 
 Identifier    ZNC-1999-54c-0735 
 Volume    54