EPR Spectrometer Pulsed, ENDOR/ELDOR

The Bruker 380E electron paramagnetic resonance (EPR) spectrometer performs pulsed and continuous-wave magnetic resonance using electron spins to selectively focus on certain types of molecules, such as free radicals and paramagnetic metal complexes, while ignoring the other components of the sample.

Research using this unique time-domain EPR spectrometer focuses on the development and application of pulsed two-dimensional methods for electronic structure and distance determinations in biological macromolecules and materials. As such, the instrument provides the researcher with the ability to:

• Determine the structure of free radicals and metal complexes of cells
• Study the weak interactions between free radicals or metal centers at different places within a sample, thus obtaining a measurement of the distance (anywhere from 2 nm to 20 nm) between these molecules
• Study proteins and molecules on surfaces to determine their orientation; from the spectra provided by the instrument, researchers can determine when the molecule or protein changes shape, how far it moves, and in which direction
• Study the spin dynamics of paramagnetic centers, an area of special interest to quantum computing materials.

This X-band instrument operates at about 9.5 gigahertz. It has the ability to perform a number of double-resonance measurements, including pulsed electron double resonance (PELDOR and DEER) and pulsed electron nuclear double resonance (ENDOR). Solid and liquid samples can be analyzed using this instrument, and cryostats are available for maintaining sample temperatures ranging from 1.8 K to above room temperature. EMSL researchers modified this instrument to include a second microwave frequency for pulsed double resonance measurements, and software enhancements were implemented to obtain pulsed double resonance measurements currently taking place.

Individuals may use this instrument independently for their research, following the necessary training, or request EMSL staff to run their samples, depending on need.

All Related Publications Related Publications

1. Imaging Consecutive Steps of O2 Reaction with Hydroxylated TiO₂(110): Identification of HO₂ and Terminal OH Intermediates.
2. Suppression of conductivity in Mn-Doped ZnO Thin Films.
3. Two Pathways for Water Interaction with Oxygen Adatoms on TiO2(110).
4. Binding and Direct Electrochemistry of OmcA, an Outer-Membrane Cytochrome from an Iron Reducing Bacterium, with Oxide Electrodes: A Candidate Biofuel Cell System.
5. Transient Mobility of Oxygen Adatoms upon O2 Dissociation on Reduced TiO2 (110).