Show simple item record

dc.contributor.authorLuo, Yu-Ran.en_US
dc.date.accessioned2014-10-21T12:35:41Z
dc.date.available1991
dc.date.issued1991en_US
dc.identifier.otherAAINN71423en_US
dc.identifier.urihttp://hdl.handle.net/10222/55248
dc.descriptionNew, simple and empirical methods have been proposed for estimating the homolytic and heterolytic dissociation energies of alkyl-X bonds, where X represents a halogen or hydrogen atom and CH$\sb3$, SiH$\sb3$, GeH$\sb3$, NH$\sb2$, PH$\sb2$, OH, SH, and C- or Si-centered groups. The uncertainties for most values estimated by these methods are within the accuracy of experimental determination ($\pm$1 kcal/mol). New and simple algorithms for estimating ionization potentials or alkyl radicals, hydrocarbons, and chloro-, bromo- and iodoalkanes have been established.en_US
dc.descriptionA new, step-by-step approach is used to attack these problems. In the first step, Pauling's semi-quantitative electronegativity (EN) scale has been replaced by the covalent potential, V$\sb{\rm x}$ = $\sb{\rm x} / \rm r\sb{\rm x}$, where n$\sb{\rm x}$ is the number of valence electrons in the bonding atom in X, and r$\sb{\rm x}$ is the covalent radius of the bonding atom. From this and the many accurate experimental results available in the literature, the rules for calculating homolytic and heterolytic dissociation energies can be devised.en_US
dc.descriptionThe new procedure correlates quantitatively with the four factors which determine the dissociation energies of alkyl-X and alkylsilyl-X bonds and energetics of species. The four factors are: (1) the new scale of EN or the covalent potential of X, V$\sb{\rm x}$; (2) the degree of methyl substitution on the alkyl radical center or the formal charge center, m; (3) the interactions between the radical center or formal charge center and the distant atoms, "the $\gamma$ effect"; and (4) the steric compression relief due to bond cleavage. The "constancy" of the bond energies of Si-H, Si-C and Si-Si bonds is explained using these factors.en_US
dc.descriptionThesis (Ph.D.)--Dalhousie University (Canada), 1991.en_US
dc.languageengen_US
dc.publisherDalhousie Universityen_US
dc.publisheren_US
dc.subjectChemistry, Physical.en_US
dc.titleHomolytic and heterolytic energies of alkyl-X bonds and ionization potentials of alkyl radicals, alkanes and haloalkanes.en_US
dc.typetexten_US
dc.contributor.degreePh.D.en_US
 Find Full text

Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record