Coordination chemical approach

Zinder, B., G. Furrer, and W. Stumm. 1986. A coordination chemical approach to the kinetics of weathering. II. Dissolution of Fe(ni) oxide. Geochim. Cosmochim. Acta 50 1861-1869. 

Tombacz. E. et al., pH-dependent aggregation state of highly dispersed alumina, titania and silica particles in aqueous medium. Prog. Colloid Polym. Sci, 98, 160, 1995. Wieland. E.. The weathering of sparingly soluble minerals—a coordination chemical approach for describing their dissolution kinetics, Ph.D. Thesis, ETH, Zurich, 1988, cited after [865]. 

Noller, H. and Vinek, H. Coordination chemical approach to catalytic oxidation reactions. J. Mol Catal 1989, 51, 285-294. 

Despite several decades of studies devoted to the characterization of Fe-ZSM-5 zeolite materials, the nature of the active sites in N20 direct decomposition (Fe species nuclearity, coordination, etc.) is still a matter of debate [1], The difficulty in understanding the Fe-ZSM-5 reactivity justifies a quantum chemical approach. Apart from mononuclear models which have been extensively investigated [2-5], there are very few results on binuclear iron sites in Fe-ZSM-5 [6-8], These DFT studies are essentially devoted to the investigation of oxygen-bridged binuclear iron structures [Fe-0-Fe]2+, while [FeII(p-0)(p-0H)FeII]+ di-iron core species have been proposed to be the active species from spectroscopic results [9]. We thus performed DFT based calculations to study the reactivity of these species exchanged in ZSM-5 zeolite and considered the whole nitrous oxide catalytic decomposition cycle [10],... 

Sulzberger, B. (1990), "Photoredox Reactions at Hydrous Metal Oxide Surfaces a Surface Coordination Chemistry Approach", in W. Stumm, Ed., Aquatic Chemical Kinetics, Wiley-lnterscience, New York, pp. 401-429. 

Another chemical approach to the chemical conversion of methane involves organometallic reactions.85-89 Interesting work with iridium complexes and other transition metal insertion reactions (rhodium, osmium, rhenium, etc.) were carried out. Even iron organometallics were studied. These reactions take place in the coordination spheres of the metal complexes, but so far the reactions are stoichiometric and noncatalytic.77 In terms of synthetic hydrocarbon chemistry, these conversions are thus not yet practical, but eventually it is expected that catalytic reactions will be achieved. 

It is clear that in detailed modeling studies, a flexible quantum chemical approach is required to accommodate the variety of electronic states which may be involved. Figure 3.23 displays free energy profiles along the ET reaction coordinate (17) for some examples of the CS and CR type. The definition of 17 and the formulation of the energy surfaces are discussed in Section 3.5.4. 

Although species of the general formulation R-P=CR2 wherein trivalent phosphorus is bound to only two (carbon) atoms have been proposed for many years as intermediates in a variety of chemical reactions, it was not until 1978 thatastable compound of this class was isolated. This effort involved the generation of a sterically hindered system with three bulky aromatic rings bound around the P=C site (equation 9) that could reversibly add hydrogen chloride. The P NMR spectrum exhibited a signal at relatively low field in accord with the postulation of such trivalent doubly coordinated phosphorus. Approaches toward this type of species have been reviewed. ... 

Sulzberger B (1990) Photoredox reactions at hydrous metal oxide surfaces A surface coordination chemistry approach. In Aquatic Chemical Kinetics. Stumm W (ed) p 401-430. New York Wiley Sulzberger B, Siffert C, Stumm W (1988) Surface coordination chemistry and redox processes— Photoinduced iron (III) oxide dissolution. Chimia 42 257-261 Swap R, Garstang M, Greco S, Talbot R, Kallberg P (1992) Saharan dust in the Amazon basin. Tellus B 44 133-149... 

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