Dissociation energy table

The reaction rate of molecular oxygen with alkyl radicals to form peroxy radicals (eq. 5) is much higher than the reaction rate of peroxy radicals with a hydrogen atom of the substrate (eq. 6). The rate of the latter depends on the dissociation energies (Table 1) and the steric accessibiUty of the various carbon—hydrogen bonds it is an important factor in determining oxidative stabiUty. 

For example, based on equation 24, it can be concluded that the isomerization reaction of H2M=CH2 to HMCH3 becomes more exothermic as M becomes heavier, due to the decrease in the M—H bond dissociation energy (Table 3) and in D , and the increase in the DSSE of the MH2 fragments. This conclusion is supported by ab initio calculations. For example, equation 24 leads to predicted isomerization energies of H2M=CH2, M=Si and Ge of 5.8 and —15.3 kcal mol 1, respectively, in good agreement with the ab initio calculated values of 4295 and —15296 kcal mol-1, respectively. 

Another characteristic property of organic halides is the bond dissociation energy. Table II lists bond energy values for carbon-halogen linkages... 

From the table of bond dissociation energies (Table -1.2, p. 21) we can calculate for each of the four halogens the AH for each of the three steps of halogenation. Since act has been measured for only q few of these reactions, let us see what tentative conclusions we can reach using only AH. 

Values of AH° can be calculated from bond dissociation energies (Table 3.1). For example, the AH° for the addition of HBr to ethene is calculated as shown here ... 

Yu-Ran Luo, Ph.D., graduated from the Urriversity of Science and Technology of China and taught at the same university He earned his doctoral degree from Dalhousie University in 1991. He has worked at the University of Ottawa, the University of Southern California, and NIST. Currently, he is a faculty member at the University of South Florida and is responsible for updating the BDE (bond dissociation energy) tables in the CRC Handbook of Chemistry and Physics. 

To see the magnetic field s effect on the chemical bond of H2, the dissociation energy (Table 13.3), quadrupole moments (Table 13.4), and the electron density under various strengths of parallel and perpendicular magnetic fields (Fig. 13.2) were calculated. Our results here are basically in agreement with previous studies on H2+ in a magnetic field [18,22,25,32]. Here, we briefly summarize our results ... 

Indeed, of special importance here is the maximum temperature to which the tar vapors are exposed before they are condensed as well as the bonds considered likely to participate in the thermolysis sequence (Benjamin et al., 1978 Miller and Stein, 1979). However, even though bond dissociation energies (Table 13.6) (Szwarc, 1950) wiU give some indication of the bonds that are most likely to be cleaved during coal pyrolysis, there are other factors involved that may give additional... 

Kolos and Wolniewicz increased the accuraty of their calculations in 1968 and excluded the first possibility. It soon turned out that the problem lay in the accuradissociation energy (Table 10.1, bold face), which was then consistent with the variational principle. 

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