Abstract
Integer-spin systems with S > 1 sometimes exhibit a ground-state 'non-Kramers (NK) doublet' in their electron paramagnetic resonance (EPR) spectra. The preferred method of studying systems with this type of EPR signal has been to use a spectrometer in which the microwave field is parallel to the applied static field (parallel-mode EPR), rather than a traditional perpendicular-mode EPR spectrometer, in order to maximize the resulting NK-EPR signal. The efficacy of parallel and perpendicular mode electron spin echo envelope modulation (ESEEM) spectroscopy on the NK doublet of azido-hemerythrin (N3Hr(red)) are compared. These results demonstrate that for this technique, the advantages of parallel-mode over perpendicular-mode ESEEM are minimal at best. A simplified form of the theory underlying the analysis of NK-ESEEM is developed to explain the observations. (C) 2000 Elsevier Science S.A.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 400-403 |
| Number of pages | 4 |
| Journal | Inorganica Chimica Acta |
| Volume | 297 |
| Issue number | 1-2 |
| DOIs | |
| State | Published - 2000 |
Funding
This work has been supported by the NSF (MCB 9507061) and from the NIH (HL 13531). We wish to thank Mr Clark E. Davoust for his technical expertise, Dr Bradley E. Sturgeon for the parallel-mode ESEEM, Professor D. Kurtz and Dr J. Nocek for the azido–hemerythrin samples. And the authors would like to acknowledge our stimulating and fruitful collaboration with Professor Stephen J. Lippard, who introduced us to the wonders of carboxylato–diiron centers.
Keywords
- Azido-hemerythrin
- Electron paramagnetic resonance
- Electron spin envelope modulation
- Non-Kramers
- Parallel-mode
- Theory
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry