Antimony-121 Mossbauer spectroscopy

Antimony-121 Mossbauer Spectroscopy Sb Mossbauer spectra of a number of antimony dithiocarbamate... 

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. 

There has been to some degree the belief that Mossbauer spectroscopy, although in principle an ideal technique for catalyst studies, for practical purposes can only be applied to problems in catalysis if the catalyst contains either iron or tin. Therefore, one of the main purposes of this review is to show how Mossbauer spectroscopy can be directly extended to many additional Mossbauer atoms or isotopes (such as antimony, europium, nickel, ruthenium, gold, and tungsten) and, perhaps more importantly, how the technique can be extended to obtain information about systems that do not contain a Mossbauer atom. ... 

The only naturally occurring isotope of phosphorus (31P) has a nuclear spin of V2 and a large magnetic moment. Nuclear magnetic resonance spectroscopy has accordingly played an extremely important role in the study of phosphorus compounds.1 For antimony, the isotope 121Sb is suitable for Mossbauer spectroscopy. 

Sb Mossbauer spectroscopy has been used to investigate the tin-antimony oxide catalysts used for selective oxidation of hydrocarbons (171). Recent investigations have been conducted to characterize FeSbO catalysts for ammoxidation of propene (172) and VSbO (173) and MoVSbNbO (174) catalysts for ammoxidation of propane. 

The antimony in the adducts SbF3 L and (C6H402)SbF L is pseudo-seven-coordinated, as proved by IR and Sb Mossbauer spectroscopy. L represents a tridentate nitrogen-containing donor ligand such as pyridine-2-carboxaldehyde-2-pyridylhydrazone, 2,2 6, 2"-terpyridine or 2,4,6-tris(2-pyridyl)-l,3,5-triazine. ... 

Tin oxide-based materials are potent oxidation and isomerization catalysts. Their bulk and surface properties, as well as their presumed mechanism in oxidation catalysis, have been reviewed (53j. Considerable uncertainty remains concerning the phase compositions, solid-solution range, and the redox behavior (Sn / Sn" vs. Sb WSb ) of these materials. Structural investigations have so far concentrated on the use of " Sn and Sb Mossbauer spectroscopy. Surprisingly, no " Sn solid-state NMR studies have appeared to date on this system, although it was recently demonstrated that isotropic " Sn chemical shifts and chemical shift anisotropies give characteristic fingerprints of the various tin coordination environments in Sn(IV) oxide compounds [54]. In situ C NMR has been used to study the double bond shift of 1-butene to t /.s-2-butene, and the subsequent cis-trans isomerization over tin antimony oxide catalysts [55 j. 

J. Stevens In Mossbauer Spectroscopy of Antimony Compounds, Chemical Mossbauer Spectroscopy (R. Herber, New York, London, 1984). 

Keywords tin, tin oxide, zinc hydroxystannate, zinc stannate, organotin compounds, antimony trioxide, alumina trihydrate, magnesium hydroxide, titanium dioxide, molybdenum trioxide, iron oxide, zinc borate, alumina, halogenated flame retardants, metal halides, thermal analysis, Mossbauer spectroscopy, fire-retardant mechanism, ultrafine powders, coated fillers. 

Mossbauer spectroscopy has not been noted in this report for some years, so it was of some interest to find that Ishiguro and co-workers have produced Sb, Fe and spectra in a detailed study on antimony-transition metal bonds in metal carbonyl derivatives of tertiary stibines. Finally, in this section, Beyer and Leary comment on energy-resolved collision-induced dissociation of Fc2(CO)/ (y = 1-9). 

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