Abstract
The 33S hyperfine structure has been observed in negatively charged cystine molecule-radicals RCH2(SS)-CH2R. The coupling, found to be axially symmetric about the SS bond, proved the orbital of the unpaired electron to be an antibonding SS σ* orbital with the spin density shared equally between 3p(σ*) orbitals of the two sulfurs. The 33S hyperfine structure could not be detected for a second radical produced by irradiation of the cystine hydrochloride crystal at 77°K, but interpretation of the proton hyperfine structure and g tensor observed by others led to the conclusion that this radical is the positively charged cystine molecule RCH2S+SCH2R with the spin density concentrated in a 3p orbital of one S and perpendicular to the SS bond.
Keywords: electron spin resonance, (RCH2SSCH2R)-/(RCH2SSCH2R)+
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Selected References
These references are in PubMed. This may not be the complete list of references from this article.
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