Rapid-scan Coherence Signals in X-band EPR Spectra of Semiquinones with Small Hyperfine Splittings

Authors

Hanan B. Elajaili, University of DenverFollow
George A. Rinard, University of DenverFollow
Zhelin Yu, University of DenverFollow
Deborah Gale Mitchell, University of DenverFollow
Richard W. Quine, University of DenverFollow
Sandra S. Eaton, University of DenverFollow
Gareth R. Eaton, University of DenverFollow

Publication Date

10-2015

Document Type

Article

Organizational Units

College of Natual Science and Mathematics, Chemistry and Biochemistry

Keywords

Semiquinone, Rapid-scan coherence, Hyperfine splitting

Abstract

Rapid-scan EPR signals for semiquinones with very-small well-resolved hyperfine splittings exhibit coherence signals at a time after passing through the EPR line that is proportional to the reciprocal of the hyperfine splitting. Such coherences are a general phenomenon due to constructive interference of the responses to transient excitation of spins by rapid scan of the magnetic field across equally spaced spin packets. Examples are shown for 2,3,5,6-tetramethoxy-1,4-benzosemiquinone with aH = 46 mG for 12 protons and for 2,5-di-t-butyl-1,4-benzosemiquinone with aH = 59 mG for 18 protons.

Publication Statement

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Recommended Citation

Elajaili, H., Rinard, G. A., Yu, Z., Mitchell, D. G., Quine, R. W., Eaton, S. S., & Eaton, G. R. (2015). Rapid-scan coherence signals in X-band EPR spectra of semiquinones with small hyperfine splittings. Journal of Magnetic Resonance (1997), 259, 20-23. DOI: 10.1016/j.jmr.2015.07.010.