Rate measurements literature compilations

All anionic transition metal formyl complexes described in the literature through the end of 1980 (21-47) are compiled in Table I. Since several of these have been prepared with more than one counterion, cations are not specified in the table. Geometric isomers are not assigned unless warranted by direct spectroscopic evidence. Also, the stability data in Table 1 should be regarded as qualitative, since decomposition rates have been shown to be dependent on both purity and counterion. When half-lives are specified, they are usually based upon measured rate constants. 

Relative rate constants for reactions of OH have been measured by competitive methods in 7-irradiated solutions where product formation or reactant destruction have been monitored. These methods have generally been of low accuracy and can sometimes be misleading because of the possible complications in the processes between the initial reaction and the final products. Several competitors that allow the competition at the initial step to be followed became available for use with the pulse radiolysis technique in 1965 (Adams et al., 1965). Most of the rate constants for OH reported in the literature have been determined by this method. Numerous rates have also been determined by pulse radiolysis in an absolute way, i.e. by directly observing the kinetics of the formation of transient absorption or of the decay of the parent compound absorption. Direct observation of OH (or of H) by pulse radiolysis cannot help in obtaining reaction rates, because the absorption is in the far ultraviolet and one can observe only the tail of this absorption which at 200-250nm has a very low extinction coefficient ( 500 M -1 cm-1) (Pagsberg et al., 1969). A review of the experimental methods and summary of the rate constants of OH reactions has recently been published (Dorfman and Adams, 1973) and another compilation of rate constants is currently being prepared (Farhataziz and Ross, 1975). 

Results found in the literature are compiled in Table 1. Investigations on secondary kinetic isotope efifects in electrophilic substitutions are included, but not measurements on acid-base equilibria and rates of side-chain groups of aromatic compounds substituted by deuterium or tritium in the aromatic nucleus. 

However, we can stsirt by searching through the chemical and astronomical literature, and strive compile an up-to-date list of measured and calculated rate constants, to which we add guesses for unknown rate coefficients which we believe to be significant. 

The purpose of this section is to summarize kinetic and mechanistic information available regarding the elementary reactions of organic sulfur-centered free radicals in the gas phase. It is not intended to serve as a critical review of the kinetic data. The ensuing discussions are intended to facilitate a mechanistic understanding of organic sulfur-centered free radical chemistry in light of available kinetic and mechanistic information. Several tables of rate coefficients are included. These tables represent a compilation of the available rate coefficient data reported in the literature. In some instances, the rate coefficients were obtained via indirect measurement techniques which relied on complex reaction mechanisms to interpret the experimental data the potential for systematic errors in such studies is significant. 

Relative intensity measurements with the same type of spectrometer of L lines for heavy elements (including Ir and Pt excited under 50 keV electrons) with similar discussions and references up to 1962 can be found in [2]. Mean probable values of K and L relative X-ray emission rates were published in [3], from compilation and least-squares fits of available experimental results with references up to November 1973 see also [4]. Blokhin etal. [5, tables 12.1 and 12.2] gave values selected from the literature, most of them up to 1977. 

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