Reactions of atoms

Tully J C 1980 Dynamics of gas-surface interactions reactions of atomic oxygen with adsorbed carbon on platinum J. Chem. Phys. 73 6333... 

First-principles models of solid surfaces and adsorption and reaction of atoms and molecules on those surfaces range from ab initio quantum chemistry (HF configuration interaction (Cl), perturbation theory (PT), etc for details see chapter B3.1 ) on small, finite clusters of atoms to HF or DFT on two-dimensionally infinite slabs. In between these... 

Hydrogen atoms ate thought to play a principal role in the mechanistic steps of many reactions, including hydrocarbon thermolysis (119). Some reactions of atomic hydrogen with olefins and paraffins ate the following (120—122) ... 

A number of chemiluminescent reactions have been studied by producing key reactants through pulsed electric discharge, by microwave dissociation, or by observing the reactions of atoms and free radicals produced in the inner cone of a laminar flame as they diffuse into the flame s cool outer cone (182,183). These are either combination reactions or atom-transfer reactions involving transfer of chlorine (184) or oxygen atoms (181,185—187), the latter giving excited oxides. 

InEq. (8-17), M represents a so-called third body. In gas phase reactions of atoms, M plays an essential role in conserving energy. The bulk molecules (reactant, products, added inert gases) play this role. (No third body need be involved in solution reactions, however, owing to the presence of the solvent.)... 

Ozone in the atmosphere is formed by the chemical reaction of atomic and molecular oxygen ... 

P. S. Skell Reactions of atoms silicon and the high-boiling metals. Direct syntheses of organometallics, pp. 215-221 (10). 

The intermediates may also be obtained in matrices by the reactions of atoms with stable compounds. This process is carried out in two stages -photodecomposition of a starting molecule leading to formation of atoms, and interaction of the atoms with other stable molecules, as, for example, in (2). 

C04-0116. The reaction of atom X with atom Y is represented in the foiiowing diagram. Write the baianced equation for this reaction. 

Reaction of Atomic Oxygen [0( P)] with Polybutadienes and Related Polymers... 

However, in humid gas (2.6 vol.% H20), a significant increase in NO removal was observed when increasing 02 inlet concentration up to 5 vol.% [26,31,36], followed by a slow decrease, as the 02 content was further increased. As the 02 concentration was increased, the rate of generation of OH and H02 radicals by reactions of atomic oxygen with H20 molecules increases. NO can be oxidized by reactions with these radicals, forming N02, HN02, and HN03 ... 

Semenov (20) has suggested that for exothermic abstration and addition reactions of atoms and small radicals, the following relation is useful. 

The important reactions of atomic hydrogen with CO and H2CO are subject to a considerable activation barrier in the gas phase 1,000 K). It has been proposed... 

The purpose of this article is to review some of the current endeavors in this developing field. To maintain brevity, the focus is on recent studies carried out in our own laboratory and in conjunction with Professor M.T. Bowers at the University of California at Santa Barbara, with emphasis on the use of kinetic energy release distributions and infrared laser multiphoton excitation to probe potential energy surfaces for the reactions of atomic metal ions with alkenes and alkanes. 

Experimental Studies of the Reactions of Atomic Metal Ions with Hydrocarbons... 

Endothermic Reactions and the Determination of Bond Dissociation Energies for Organometallic Fragments. The reaction of atomic nickel ion with molecular hydrogen to yield NiH+is substantially endothermic. Reaction cross sections for this process, measured using the ion beam apparatus shown in Figure 1, are displayed in Figure 3 for reactions 1 and 2 with HD as the neutral. 

Among the transfer and exchange of non-metals, the reactions of atomic oxygen, O, at low potential are unusual in that transport is not required. H20 carries O everywhere but it is not by itself active in O-incorporation into carbon frameworks. It is observed that fixed Mo (W) coenzymes have always been used as catalysts in the oxygen atom transfer from H20 to aldehydes reversibly. 

Herron, J.T., Huie, R.E. (1973) Rate constants for the reactions of atomic oxygen (3P) with organic compounds in the gas phase. J. Phys. Chem. Ref. Data 2, 467-518. 

A comparative analysis of the kinetics of the reactions of atoms and radicals with paraffinic (R1 ), olefinic (R2H), and aromatic alkyl-substituted (R3H) hydrocarbons within the framework of the parabolic model permitted a new important conclusion. It was found that the tt-C—C bond occupying the a-position relative to the attacked C—H bond increases the activation energy for thermally neutral reaction [11]. The corresponding results are presented in Table 6.9. 

The reactions of atoms or radicals with silicon hydrides, germanium hydrides, and tin hydrides are the key steps in formation of the metal-centered radicals [Eq. (1)]. Silyl radicals play a strategic role in diverse areas of science, from the production of silicon-containing ceramics to applications in polymers and organic synthesis.1 Tin hydrides have been widely applied in synthesis in radical chain reactions that were well established decades ago.2,3 Germanium hydrides have been less commonly employed but provide some attractive features for organic synthesis. 

As with silicon hydrides, the reaction of atoms or radicals with germanium hydrides is the key step for the majority of reactions forming germyl radicals. However, kinetic data for the reactions of organic radicals with germanium hydrides in solution are limited to carbon- and oxygen-centered radicals. 

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