Gold characterization

DG Pribnow, MB Mayfield, VJ Nipper, JA Brown, MH Gold. Characterization of a cDNA encoding a manganese peroxidase, from the lignin-degrading basidiomycete Phanerochaete chrysosporium. J Biol Chem 264 5036-5040, 1989. 

Park, S. and M.J. Weaver, A versatile surface modification scheme for attaching metal nanoparticles onto gold Characterization by electrochemical infrared spectroscopy. Journal of Physical Chemistry B, 2002. 106(34) pp. 8667-8670... 

The development of scanning probe microscopies and x-ray reflectivity (see Chapter VIII) has allowed molecular-level characterization of the structure of the electrode surface after electrochemical reactions [145]. In particular, the important role of adsorbates in determining the state of an electrode surface is illustrated by scanning tunneling microscopic (STM) images of gold (III) surfaces in the presence and absence of chloride ions [153]. Electrodeposition of one metal on another can also be measured via x-ray diffraction [154]. 

Metal surfaces in motion have also been characterized by STM, one of the clearest examples bemg tire surface diflfiision of gold atoms on Au(l 11) [29] (figure Bl.19.7). Surface diflfiision of adsorbates on metals can be followed [30] provided that appropriate cooling systems are available, and STM has been successfiilly employed to follow the 2D dendritic growtli of metals on metal surfaces [31]. 

Monolayers of alkanetliiols adsorbed on gold, prepared by immersing tire substrate into solution, have been characterized by a large number of different surface analytical teclmiques. The lateral order in such layers has been investigated using electron [1431, helium [144, 1451 and x-ray [146, 1471 diffraction, as well as witli scanning probe microscopies [122, 1481. Infonnation about tire orientation of tire alkyl chains has been obtained by ellipsometry [149], infrared (IR) spectroscopy [150, 151] and NEXAFS [152]. 

Porter M D, Bright T B, Allara D L and Chidsey C E D 1987 Spontaneously organized molecular assemblies. 4. Structural characterization of normal-alkyl thiol monolayers on gold by optical ellipsometry, infrared-spectroscopy, and electrochemistry J. Am. Chem. Soc. 109 3559-68... 

Lenk T J, Hallmark V M, Rabolt J F, Haussling L and Ringsdorf H 1993 Formation and characterization of self-assembled films of sulphur-derivatized poly(methyl methacrylates) on gold Macromolecules 26 1230-7... 

Grabar K C ef a/1997 Nanoscale characterization of gold colloid monolayers—a comparison of four techniques Anal. Chem. 69 471... 

Therefore, monolayers may consist of two different chemisorption modes ordered in different domains, simultaneously coexisting homogeneous clusters, each characterized by a different conformer in their unit cell. This may explain the observation of 2D Hquid in butane- and hexanethiolate monolayers on gold (278), where VDW interactions do not provide enough cohesive energy to allow for small domains to coexist as a 2D soHd. 

Gold(III) iodide has not been definitely characterized in the solid state substances with this formula in the solid state are probably gold(I) polyiodides Au+If AuI3 has also been detected in the gas phase (mass spectra). 

The higher fluorides of gold, AuF5 and AuF7, have been reported the former is well characterized [28] ... 

AuCN has a similar structure to AgCN and likewise dissolves in excess cyanide to form Au(CN)J this is important in the extraction of gold. It has been characterized as various salts (Tl, K, Bu4N, Cs) with Au-C 1.964A (Bu4N salt [91]). The thallium salt has short Au-Au (3.10A) and Au-Tl (3.50 A) interactions extended-Huckel calculations indicate the importance of relativistic effects in these covalent interactions. Isocyanides form stable complexes ... 

The Global Initiative for Chronic Obstructive Lung Disease (GOLD) has defined COPD as a disease state characterized by airflow limitation that is not fully... 

A structurally characterized gold complex with a C5HPh4 ligand Au(r C5HPh4)(PPh3) (46a) was reported [66], An unusual trinuclear cluster 46b derived therefrom was also characterized by X-ray structural analysis. 

Recently a further study of these reactions has been described (154). The compound originally characterized by Joshi et al. as Mn(CNCgH5)5Br was shown to be a mixture of [Mn(CNC4Hj)4]Br and [MnCO(CNCj-Hj)j]Br, by analyses and conductivity data. The white color reported for this complex is in accord with this new formulation all of the other covalent complexes are yellow or gold. In view of the incorrect characterization of this complex, the isolation of the new complex Mn(CNC6H5)5Cl from... 

Metallation and oxymetallation reactions have been observed with the salts of only a few metals, namely mercury(II) (66, 67), thallium(III) (66,67), lead(IV) (66, 67), palladium(II) (100), gold(III) (63), and platinum-(II) (29). These facts correlate well with what Chatt (1) has termed class b, and Pearson (130) has called "soft acid character. Soft acids are characterized by low charge, large size, and, often, d electrons in their outer shell. No class b metal is known, in fact, which contains fewer than five d... 

Mossbauer spectroscopy is a specialist characterization tool in catalysis. Nevertheless, it has yielded essential information on a number of important catalysts, such as the iron catalyst for ammonia and Fischer-Tropsch synthesis, as well as the CoMoS hydrotreating catalyst. Mossbauer spectroscopy provides the oxidation state, the internal magnetic field, and the lattice symmetry of a limited number of elements such as iron, cobalt, tin, iridium, ruthenium, antimony, platinum and gold, and can be applied in situ. 

Gregory BW, Suggs DW, Stickney JL (1991) Conditions for the deposition of CdTe by electrochemical atomic layer epitaxy. J Electrochem Soc 138 1279-1284 Suggs DW, Stickney JL (1991) Characterization of atomic layers of tellurium electrodeposited on the low-index planes of gold. J Phys Chem 95 10056-64 Suggs DW, Stickney JL (1993) Studies of the structures formed by the alternated electrodeposition of atomic layers of Cd and Te on the low-index planes of Au. 1. LEED and Auger studies. Surf Sci 290 362-374... 

Rieble S, DK Joshi, MH Gold (1994) Purification and characterization of a 1,2,4-trihydroxybenzene... 

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