Zinc, single crystal formation

Diethylenetriamineacetic acid has been used in the formation of homodinuclear zinc complexes with the bridging imidazole. The crystal structure of [LZn(imidazolate)ZnL]C104 was obtained. The magnetics of the heterodinuclear Cu-Zn complex were studied and single crystal EPR of the Zn2 dimer doped with the CuZn dimer.139... 

Methyl pyruvate thiosemicarbazone in the presence of zinc chloride or acetate resulted in the formation of complexes with the ligand hydrolyzed or transesterified. The complexes with pyruvate thiosemicarbazone, ZnL2, or ethyl pyruvate thiosemicarbazone, ZnLCl2 were structurally characterized by single-crystal X-ray crystallography showing respectively a distorted octahedral and distorted square pyramidal geometry.874... 

In the experiment, ZnCcP is produced by laser photolysis, then transient absorption spectroscopy follows the formation (k ) and decay (/Ceb) of ZnCcP + in wild-type and mutant crystals. Kang and Crane have studied the effects of interface mutations on electron transfer rates in single crystals using complexes between a zinc-substituted cytochrome c peroxidase (ZnCcP) and site-directed mutants of yeast cytochrome c (yCc).The mutants replaced the... 

Compound 325 is the taurine derivative of clathridine (a very stable zinc complex obtained from Clathrina clathrus) [240] and was isolated from the sponge Leucetta microrhaphis. Compound 325 is (9E)-clathridine 9-Ar-(2-sulfoethyl)imine and its structure was deduced by spectroscopic and chemical analysis, and confirmed by single crystal X-ray analysis. The taurine residue appears to sterically inhibit the formation of the zinc complex [241],... 

Virion templates of TMV were also used in combination with different synthetic routes for CdS, PbS, and Fe oxide nanoparticles. Nanoparticle-virion tubules were prepared by reacting a buffered solution of TMV in CdCl2 (pH 7) or TMV in Pb(N03)2 (pH 5) with H2S gas. The formation of metal sulfide nanoparticles occurred over 6 hours as observed by a uniform coating of CdS and PbS nanocrystals on the TMV surface from TEM analysis. Selected area electron diffraction of the mineralized products indicated a zinc blende crystal stracture for CdS particles and a rock salt structure for single domain PbS nanocrystals. The iron oxide nanoparticles were mineralized by the TMV templates by the oxidative hydrolysis of an Fe VFe acidic solution with NaOH. Consequently, a mineral coating of irregular ferrihydrite particles grew on the surface to a thickness of 2 nm. 

The octa-alkyl porphycenes are also able to support the formation of metal(II) complexes. Examples of these include the nickel(II) complex of octamethylpor-phycene (3.69) and the nickel(II) and zinc(II) complexes of octaethylporphycene (3.70 and 3.71). As shown by single crystal X-ray diffraction data, incorporation of divalent zinc into octaethylporphycene results in the formation of a nearly planar structure (Figure 3.1.13). Considering the somewhat non-planar nature of the starting metal-free system 3.28, the insertion of this cation apparently serves to enforce a marked increase in ligand planarity. 

Wu et al. 1998). A detailed single-crystal study of zinc acetate has indicated that although the CSA effects in this compound are small, they significantly affect the value of xq (Vosegaard et al. 1999). The 2 inequivalent octahedral Zn sites in zinc formate dihydrate have been studied by Zn NMR, which indicates that although their isotropic chemical shifts differ by only 10 ppm, their Xq values differ by more than 50% (Larsen et al. 1999). The Zn MAS NMR spectrum of K2[Zn(CN)4] has also been recorded as part of a study of potassium tetracyanometallates in which the CN ligand was partially enriched in C (Wu et al. 1995). 

As to the thermodynamically controlled formation of acyclic polymeric assemblies in solution, there are only a few examples in the literature. The main problems are due to a) competition with cyclization processes b) low association constants c) low solubility of the oligomers. In fact the first reported polymeric assembly in solution made of zinc 5-(4-pyridyl)-10,15,20-triphenylporphyrin (ZnPyTPP) units [47], actually consists, as successively demonstrated, of a cyclic tetramer (Sect. 3.3). The linear polymer, however, was unambiguously detected in the solid state by X-ray analysis of a ZnPyTPP single crystal [47]. This is one of the first examples in the literature of met-alloporphyrins, illustrating the fact that the stability of an assembly may be strongly dependent on the aggregation state. 

A.S. Lipton, M.D. Smith, R.D. Adams, P.D. Ellis, sohd-state and single-crystal NMR spectroscopy and X-ray crystal structure of zinc formate dihydrate, J. Am. Chem. Soc. 124 (2002) 410-414. 

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