Structure and dynamics of the lowest triplet state in p-benzoquinone

Abstract

Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.

Synthetic methodologies in organic chemistry involving incorporation of [17O] and [18O] isotopes

“…The [ 17/18 O]‐labeled quinones were prepared by shaking a benzene solution of the quinone, containing enriched water, in an evacuated tube for about 10 days. Boykin et al .…”

Methyl group tunneling rotation in the lowest nπ* state of toluquinone. An optically detected ENDOR, LAC and CR study

“…We have tried to discriminate between these two possibilities by calculating the anisotropic hyperfine interaction of the methyl protons by using the calculated gross atomic spin densities of PBQ [3] and Table 1 Hyperfie data from ENDOR transitions in the l-1, A, state. The isotropic hyperfme interaction is: $,Aio = 5.08 (0.27) Bf Hz.…”

“…For the hyperfine interaction of the methyl group protons with unpaired electron spin density in TQ no such a simple relationship exists. This is due to the fact that in this case a methyl proton interacts with the unpaired spin-density of the n-type (mainly localized at oxygen [3]) and also with the unpaired spin-density of the n-type which is delocalized 131. Note that in the case of TQ this leads to a significant contribution of the isotropic and misorropic hyperfie interaction to A*, in contradistinction with the case of a molecular radical, where the isotropic hyperfine interaction contribution to A" is dominant.…”