Continuous-wave EPR at 275GHz: application to high-spin Fe(3+) systems
- Citation:
- Continuous-wave EPR at 275GHz: application to high-spin Fe(3+) systems, Mathies, G., Blok H., Disselhorst J. A., Gast P., van der Meer H., Miedema D. M., Almeida R. M., Moura J. J., Hagen W. R., and Groenen E. J. , J Magn Reson, May, Volume 210, Number 1, p.126-32, (2011)
Abstract:
The 275GHz electron-paramagnetic-resonance spectrometer we reported on in 2004 has been equipped with a new probe head, which contains a cavity especially designed for operation in continuous-wave mode. The sensitivity and signal stability that is achieved with this new probe head is illustrated with 275GHz continuous-wave spectra of a 1mM frozen solution of the complex Fe(III)-ethylenediamine tetra-acetic acid and of 10mM frozen solutions of the protein rubredoxin, which contains Fe(3+) in its active site, from three different organisms. The high quality of the spectra of the rubredoxins allows the determination of the zero-field-splitting parameters with an accuracy of 0.5GHz. The success of our approach results partially from the enhanced absolute sensitivity, which can be reached using a single-mode cavity. At least as important is the signal stability that we were able to achieve with the new probe head.
Notes:
1096-0856 (Electronic)1090-7807 (Linking)Journal ArticleResearch Support, Non-U.S. Gov't
