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Anionic gold
Joseph J. Lagowski
Gold Bulletin , 1983, DOI: 10.1007/BF03216571
Abstract: In recent years, research into the formation and properties of metallic anions in solution has led to interesting advances in our knowledge of alkali metal and gold anions. The latter may have possible uses in the separation of gold from base metals and in refining applications.
Gold complexes with
DA Pichugina,NE Kuz'menko,AF Shestakov
Gold Bulletin , 2007, DOI: 10.1007/BF03215567
Abstract: The reactions of methane with the gold complexes [Au(OH)] , [Au(OCH3)4] , [Au(O(CO)2O2] and [Au(O2CH)2]+, [AuI(acac)], [AuIII(acac)2]+ (acac-acetylacetonato) were studied using the DFT/PBE method with the SBK basis set. High activation barriers were obtained for the electrophilic substitution in [Au(OH)] , [Au(OCH3)4] , [Au(O(CO)2O)2]-and [AuIII(acac)2]+ complexes, which excludes the possibility that these reactions might proceed under mild conditions. The reactions of the [Au(HCO2)2]+ and [AuI(acac)] complexes with methane have rather low energy barriers and proceed through the formation of an intermediate complex. The alternative mechanism of methane oxidation with a gold complex in the presence of oxygen is simulated.
Gold complexes for nonlinear optics
Mark G Humphrey
Gold Bulletin , 2000, DOI: 10.1007/BF03215485
Abstract: The nonlinear optical (NLO) properties of gold complexes are reviewed. Experimental procedures which have been used to determine NLO behaviour of gold complexes are summarized, structure / NLO property correlations are presented, and the potential of gold complexes for nonlinear optics is discussed.
The sulphito complexes of gold
Paul C. Hydes,Harry Middleton
Gold Bulletin , 1979, DOI: 10.1007/BF03215106
Abstract: A new nitro-sulphito gold electrolyte has advantages over available commercial sulphito electrolytes in terms of stability, simplicity of control and the minimum non-porous deposit thickness. In describing its development, the authors review what is known of gold sulphite complexes and their use in gold plating baths.
Luminescence in gold-heterometal complexes
Eduardo J Fernández,Antonio Laguna,José M López-de-Luzuriaga
Gold Bulletin , 2001, DOI: 10.1007/BF03214803
Abstract: There are four types of gold-heteroatom complexes which display luminescence: dinuclear complexes, triand tetranuclear complexes, polymeric chains, and clusters. The present state of knowledge on the preparation and properties of each of these types is summarized here.
Gold complexes and activated carbon
Gloria J. McDougall,Robert D. Hancock
Gold Bulletin , 1981, DOI: 10.1007/BF03216558
Abstract: Exciting new developments are taking place in the extractive metallurgy of gold, which are based upon the adsorption of the metal or its complexes on carbon and subsequent elution. Despite the efforts of investigators over a period of almost 70 years, however, the mechanisms of the adsorption and elution processes have not yet been established unequivocally. The literature relating to them is reviewed here.
Gold recovery by galvanic stripping of an anionic organic extractant
Lacerda, D.F.C.;Pereira, J.F.G.;Martins, A.H.;
Brazilian Journal of Chemical Engineering , 2001, DOI: 10.1590/S0104-66322001000200008
Abstract: the galvanic stripping technique for metal recovery uses commercial organic extractants containing a metal to be recovered. the organic phase is placed in contact with a solid metal reducer that allows electrochemical reactions to occur. one product of these reactions is a metal layer deposited on the surface of the reducer consisting of reduced species desorbed from the organic phase. another product is metal ions from the reducer adsorbed onto the organic phase. this work presents results for gold recovery by galvanic stripping of strong-base anionic extractants of a quaternary amine salt, aliquat336?, in xylene using solid zinc as the metal reducer. the parameters studied were contact time for the organic phase containing gold and the samples of the reducing zinc metal, temperature of the system, gold concentration in the organic phase and type of stirring used in the galvanic stripping system. experiments showed results higher than 28% of gold recovery and an adherent film of gold on the zinc surface. the arrhenius plot for gold recovery from the organic extractant suggests a change in the rate- controlling step from mixed control to diffusion control with increasing temperature in the range of 20 to 50oc.
Gold recovery by galvanic stripping of an anionic organic extractant  [cached]
Lacerda D.F.C.,Pereira J.F.G.,Martins A.H.
Brazilian Journal of Chemical Engineering , 2001,
Abstract: The galvanic stripping technique for metal recovery uses commercial organic extractants containing a metal to be recovered. The organic phase is placed in contact with a solid metal reducer that allows electrochemical reactions to occur. One product of these reactions is a metal layer deposited on the surface of the reducer consisting of reduced species desorbed from the organic phase. Another product is metal ions from the reducer adsorbed onto the organic phase. This work presents results for gold recovery by galvanic stripping of strong-base anionic extractants of a quaternary amine salt, ALIQUAT336 , in xylene using solid zinc as the metal reducer. The parameters studied were contact time for the organic phase containing gold and the samples of the reducing zinc metal, temperature of the system, gold concentration in the organic phase and type of stirring used in the galvanic stripping system. Experiments showed results higher than 28% of gold recovery and an adherent film of gold on the zinc surface. The Arrhenius plot for gold recovery from the organic extractant suggests a change in the rate- controlling step from mixed control to diffusion control with increasing temperature in the range of 20 to 50oC.
Adsorption of Ethylene on Neutral, Anionic and Cationic Gold Clusters  [PDF]
Andrey Lyalin,Tetsuya Taketsugu
Physics , 2009, DOI: 10.1021/jp909505y
Abstract: The adsorption of ethylene molecule on neutral, anionic and cationic gold clusters consisting of up to 10 atoms has been investigated using density-functional theory. It is demonstrated that C2H4 can be adsorbed on small gold clusters in two different configurations, corresponding to the pi- and di-sigma-bonded species. Adsorption in the pi-bonded mode dominates over the di-sigma mode over all considered cluster sizes n, with the exception of the neutral C2H4-Au5 system. A striking difference is found in the size-dependence of the adsorption energy of C2H4 bonded to the neutral gold clusters in the pi and di-sigma configurations. The important role of the electronic shell effects in the di-sigma mode of ethylene adsorption on neutral gold clusters is demonstrated. It is shown that the interaction of C2H4 with small gold clusters strongly depends on their charge. The typical shift in the vibrational frequencies of C2H4 adsorbed in the pi- and the di-sigma configurations gives a guidance to experimentally distinguish between the two modes of adsorption.
Water-soluble and water-stable Gold(I), Gold(II) and Gold(III) phosphine complexes: The early years
Fabian Mohr,Sergio Sanzb,Elena Vergarab,Elena Cerradab,Mariano Laguna
Gold Bulletin , 2006, DOI: 10.1007/BF03215556
Abstract: This article briefly reviews the still rather limited knowledge of the chemistry, structures, reactions and applications of gold complexes containing water-soluble phosphine ligands sorted by gold oxidation state.
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