Crystal structures copper

Front cover image Hydrates are compounds in which a specific number of water molecules are integral parts of the crystal structure. Copper(ll) sulfate pentahydrate is a beautiful blue substance that is used in countless products, from herbicides to dyes to fireworks. When it is heated strongly, a chemical reaction occurs, and the hydrate loses water molecules to become a different comfx und— white, crumbly, anhydrous copper ll) sulfate. 

Fig. 8. Sketch of the zinc coordination polyhedron obtained from the 2SOD crystal structure. Copper and zinc are represented by spheres of arbitrary radius.

Calculations of this type are carried out for fee, bcc, rock salt, and hep crystal structures and applied to precursor decay in single-crystal copper, tungsten, NaCl, and LiF [17]. The calculations show that the initial mobile dislocation densities necessary to obtain the measured rapid precursor decay in all cases are two or three orders of magnitude greater than initially present in the crystals. Herrmann et al. [18] show how dislocation multiplication combined with nonlinear elastic response can give some explanation for this effect. 

Reductive coupling reaction of fluonnated vinyl iodides or bromides has been used as a route to fluorinated dienes [246, 247, 248, 249, 250. Generally, the vinyl iodide is heated with copper metal in DMSO or DMF no 1 ntermediate perfluorovmy I-copper reagent is detected. Typical examples are shown m equations 163-165 [246, 247, 249. The X-ray crystal structure of perfluorotetracyclobutacyclooctatetraene, prepared via coupling of tetrafluoro-l,2-diiodocyclobutene with copper, is planar... 

However, just as two liquids may be completely miscible and form a complete range of solutions from one pure liquid to the other, so certain metals, for example copper and nickel, exhibit complete solid solubility over the whole range of compositions from pure copper to pure nickel. Clearly for two metals to be soluble in each other over the whole compositional range, they must have the same crystal structure, i.e. they must be isomorphous. 

Lundberg and Savborg [222] reported that the crystal structure of CuNb03F is composed of Nb(0, F)6 octahedrons linked via two shared comers. The linked octahedrons form zig-zag chains along the c axis. The chains are connected to one another via copper atoms, each of which is surrounded by four anions that form a four-sided structure and two additional anions positioned at a greater distance from the copper atom. Fig. 35 shows the structural elements of CuNb03F. 

Models for copper-protein interaction based on solution and crystal structure studies. R. Osterberg, Coord. Chem. Rev., 1974,12, 309-347 (130). 

The differing malleabilities of metals can be traced to their crystal structures. The crystal structure of a metal typically has slip planes, which are planes of atoms that under stress may slip or slide relative to one another. The slip planes of a ccp structure are the close-packed planes, and careful inspection of a unit cell shows that there are eight sets of slip planes in different directions. As a result, metals with cubic close-packed structures, such as copper, are malleable they can be easily bent, flattened, or pounded into shape. In contrast, a hexagonal close-packed structure has only one set of slip planes, and metals with hexagonal close packing, such as zinc or cadmium, tend to be relatively brittle. 

Because the metallic radii of the d-block elements are all similar, they can form an extensive range of alloys with one another with little distortion of the original crystal structure. An example is the copper-zinc alloy used for some copper coins. Because zinc atoms are nearly the same size as copper atoms and have simi-... 

Dithiocarbamate complexes of copper have been sythesized at a high rate. Reports of new complexes include the morpholine-4- (44), thio-morpholine, AT-methylpiperazine-4-, and piperidine- (291) dithiocarba-mates. Novel, polymeric complexes of the type Cu(pipdtc)2 (CuBr) in = 4, or 6) and Cu(pipdtc)2 (CuCl)4 have been prepared by reactions of[Cu(pipdtc)2] with the respective copper halide in CHCla-EtOH (418). The crystal structures of the polymers are known to consist of sheets of individual [Cu(pipdtc)2] molecules linked to polymeric CuBr chains via Cu-S bonds. A series of copper(I) dtc complexes have been the subject of a Cu and Cu NQR-spectral study (440). 

The crystal structure of [Cu(Me2dtc)2] shows that it possesses a center of S3rmmetry, with the copper octahedrally co-ordinated to six S atoms, two Cu-S bonds being longer than the other four (424). Choi and Wasson (425) showed that there is only Cu-S bonding in [Cu(acdc)2] (acdc = 2-amino-l-cyclopentadienyl-l-dithiocarboxylate). 

For crystallographic data, see Table I. The compounds of the type CuTeX and CuTe X (X = Cl, Br, or I), respectively, are isotypic, and their crystal structures have been determined. Copper has the oxida-... 

These authors further described the synthesis and resolution (by chiral HPLC) of a new C2-symmetric planar-chiral bipyridine ligand [43] (see structure 35 in Scheme 18). They obtained an X-ray crystal structure of the corresponding copper complex proving a bidentate complexation. This system led to high diastereo- (up to 94%) and enantioselectivity (up to 94%) in the... 

The ruthenium-copper and osmium-copper systems represent extreme cases in view of the very limited miscibility of either ruthenium or osmium with copper. It may also be noted that the crystal structure of ruthenium or osmium is different from that of copper, the former metals possessing the hep structure and the latter the fee structure. A system which is less extreme in these respects is the rhodium-copper system, since the components both possess the face centered cubic structure and also exhibit at least some miscibility at conditions of interest in catalysis. Recent EXAFS results from our group on rhodium-copper clusters (14) are similar to the earlier results on ruthenium-copper ( ) and osmium-copper (12) clusters, in that the rhodium atoms are coordinated predominantly to other rhodium atoms while the copper atoms are coordinated extensively to both copper and rhodium atoms. Also, we conclude that the copper concentrates in the surface of rhodium-copper clusters, as in the case of the ruthenium-copper and osmium-copper clusters. 

The most important information about the nanoparticles is the size, shape, and their distributions which crucially influence physical and chemical properties of nanoparticles. TEM is a powerful tool for the characterization of nanoparticles. TEM specimen is easily prepared by placing a drop of the solution of nanoparticles onto a carbon-coated copper microgrid, followed by natural evaporation of the solvent. Even with low magnification TEM one can distinguish the difference in contrast derived from the atomic weight and the lattice direction. Furthermore, selective area electron diffraction can provide information on the crystal structure of nanoparticles. 

Bertrand T, Jolivalt C, Briozzo P, Caminade E, Joly N, Madzak C, Mougin C. 2002. Crystal structure of a four-copper laccase complexed with an arylamine Insights into substrate recognition and correlation with kinetics. Biochemistry 41 7325-7333. 

Hakulinen N, Kiiskinen LL, Kruus K, Saloheimo M, Paananen A, Koivula A, Rouvinen J. 2002. Crystal structure of a laccase from Melanocarpus albomyces with an intact trinuclear copper site. Nature Struct Biol 9 601-605. 

Piontek K, Antorini M, Choinowski T. 2002. Crystal structure of a laccase from the fungus Trametes versicolor at 1.90 A resolution containing a full complement of coppers. J Biol Chem277 37663-37669. 

K. Nomoto, Y. Mino, T. Ishida, H. Yoshioka, N. Ota. M. Inoue, S. Tagaki, and T. Takemoto, X-ray crystal structure of the copper(ll)complex of mugineic acid, a naturally occuring metal chelator of graminaceous plants. J. Client. Soc. Client. Contmun. 338 (1981). 

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