Kinetic energy release distributions for

Figure 8. Characteristic shapes of kinetic energy release distributions for different model potential energy surfaces.

Figure 9. Kinetic energy release distributions for several dehydrogenation reactions. Data from reference 38.

In contrast to the results obtained for dehydrogenation reactions, kinetic energy release distributions for alkane elimination processes can usually be fit with phase space theory. Results for the loss of methane from reaction 9 of Co + with isobutane are shown in Figure 10b. In fitting the... 

The success of the phase space theory in fitting kinetic energy release distributions for exothermic reactions which involve no barrier for the reverse reaction have led to the use of this analysis as a tool for deriving invaluable thermochemical data from endothermic reactions. This is an important addition to the studies of endothermic reactions described above. As an example of these studies, consider the decarbonylation reaction 11 of Co+ with acetone which leads to the formation of the... 

The application of newer methods to studies of gas phase organometallic reactions will lead to the development of routine techniques for determination of the thermochemistry of organometallic species. The examples discussed above demonstrate that an analysis of kinetic energy release distributions for exothermic reactions yields accurate metal ligand bond dissociation energies. This can be extended to include neutrals as well as ions. For example, reaction 15 has been used to determine accurate bond dissociation energies for Co-H and C0-CH3 (57). 

Detailed Analysis of Kinetic Energy Release Distributions for Type I Surfaces using Phase Space Theory. The model for the statistical phase space theory calculations(S) begins with Equation 1, where is the flux through the... 

Figure 4. Experimental and theoretical kinetic energy release distributions for loss of H2 from Co(isobutane). The calculated distribution assumes no activation barrier for the reverse process.

Figure 11. Kinetic energy release distribution for metastable loss of CH4 from nascent Co(C3Hg)+ collision complexes. The "unrestricted" phase space theory curve assumes the entrance channel contains only an orbiting transition state, the exit channel has only an orbiting transition state (no reverse activation barrier), and there are no intermediate tight transition states that affect the dynamics. The "restricted" phase space theory calculation includes a tight transition state for insertion into a C-H bond located 0.08 eV below the asymptotic energy of the reactants.

Figure 3 The PEPICO TOF distribution of C2H5 ions from energy selected C2H5l + ions at various energies above the dissociation limit for - loss. The solid lines that fit the experimental points are single energy release distributions. From these data, the whole distribution of product translational energies could be determined. Reproduced with permission from Baer T, Buchler U and Klots TCE (1980) Kinetic energy release distributions for the dissociation of internal energy selected C2H5l + ions. Journal de Chimie Physique 77 739-743.

Baer T, Buchler U and Klots CE (1980) Kinetic energy release distributions for the dissociation of internal energy selected C2H5P ions. Journal de Chemie Physique 77 739-743. 

Under certain circumstances, it has been shown that the 8 2 reactions of such stable intermediates can be initiated using infrared laser light. The reaction can be also activated by collisions with argon atoms. The kinetic energy release distribution for metastable dissociation of the Cr(CH3Br) species has been measured, " which may serve as a model for the intermediate in the bimolecular reaction (1.8.1). 

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