Continuous-wave EPR at 275 GHz: Application to high-spin Fe3+ systems
Publication year: 2011
Source: Journal of Magnetic Resonance, In Press, Accepted Manuscript, Available online 11 March 2011
G., Mathies , H., Blok , J.A.J.M., Disselhorst , P., Gast , H., van der Meer , ...
The 275 GHz 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 275 GHz continuous-wave spectra of a 1 mM frozen solution of the complex Fe(III)-ethylenediamine tetra-acetic acid (EDTA) and of 10 mM frozen solutions of the protein rubredoxin, which contains Fe3+ 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...
Graphical abstract
*Graphical abstract:**Research Highlights:*? 275 GHz continuous-wave EPR spectroscopy on high-spin Fe3+ systems using a specialized single-mode cavity. ? Sensitivity and signal stability are illustrated on dilute solutions of Fe(III)-EDTA and rubredoxin. ? Zero-field-splitting parameters and g-anisotropy were determined accu-rately by simulation of the spectra
Source:
Journal of Magnetic Resonance