F. W. Pijpers, M. R. Arick, B. Hendriks
1964
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0
Influential Citations
10
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Journal
Molecular Physics
Abstract
The E.P.R. spectra of the monovalent positive and negative ions of 1,2,3,6,7,8-hexahydropyrene reveal an alternating line broadening, caused by the non-synchronized motion of the two aliphatic bridges in the molecule. When this motion is described by the modified Bloch equations, using a four-sites jump model, spectra are obtained which agree quite well with the experimental ones. The potential barrier for the conformational interconversion can be calculated from the temperature dependence of the lifetime of each configuration and is found to be 10·0±0·4 kcal mole-1 for the radical anion and 3·5±0·4 kcal mole-1 for the radical cation. The inversion rate at 0°C equals 2·8 × 106 s-1 for the anion and 4·2 × 106s-1 for the cation.