Accession Number:

AD0255802

Title:

THEORETICAL INTERPRETATION OF CARBON-13 HYPERFINE INTERACTIONS IN ELECTRON SPIN RESONANCE SPECTRA

Descriptive Note:

Corporate Author:

COLUMBIA UNIV NEW YORK DEPT OF CHEMISTRY

Personal Author(s):

Report Date:

1961-05-01

Pagination or Media Count:

1.0

Abstract:

A quantitative theory of the isotropic electronnuclear spin interactions of C-13 in pi-electron radicals is presented and applied to the hyperfine splittings observed in the electron spin resonance spectra of these substances. The theory predicts both the magnitude and sign of the hyperfine splittings and is readily applied to a variety of compounds. For the methyl radical, the measured C-13 splitting is shown to be consistent with a planar model and limits the deviation from planarity to less than or approximately equal to 5 degrees. The theory provides a useful criterion for the validity of approximate wave functions. The sigma-pi interaction parameters are shown to depend on the bond length, the type of hybridization, and on the nature of the bonding atoms. For pi-electron systems, the results demonstrate that the magnitude of the sigma-pi exchange energy is a small fraction of the total energy. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE