Category Archives: High-Field EPR

[NMR] Dates for the diary: 53rd ESR Group Conference in Manchester

Dear Colleagues,

the next conference in the long series of Electron Spin Resonance meetings organised by the ESR Group of the Royal Society of Chemistry will take place in Manchester between 29th March and 2nd April 2020:

http://www.esr-group.org/conferences/2020-conference-manchester/

The Meeting is the oldest EPR Spectroscopy conference in the world, as well as the occasion on which the EPR Spectroscopy Bruker Prize is awarded to eminent EPR scientists, Bruker Thesis Prize is given for the best PhD thesis in the preceding two years, and the JEOL Student Prize is awarded for the best student research work presented at the Conference.

The registration will open in November.

Best wishes,

Ilya.

—————————————–

Dr Ilya Kuprov FRSC

Associate Professor of Chemical Physics

Secretary to the RSC ESR Spectroscopy Group

Associate Editor, Science Advances

Office 3041, Building 30,

School of Chemistry, FNES,

University of Southampton,

Southampton, SO17 1BJ, UK.

Tel: +44 2380 594 140

Email: i.kuprov@soton.ac.uk

Web: http://spindynamics.org

—————————————–

====================================

This is the AMPERE MAGNETIC RESONANCE mailing list:

http://www.drorlist.com/nmrlist.html

NMR web database:

http://www.drorlist.com/nmr.html

1H high field electron-nuclear double resonance spectroscopy at 263 GHz/9.4 T

Tkach, Igor, Isabel Bejenke, Fabian Hecker, Annemarie Kehl, Müge Kasanmascheff, Igor Gromov, Ion Prisecaru, Peter Höfer, Markus Hiller, and Marina Bennati. “1H High Field Electron-Nuclear Double Resonance Spectroscopy at 263 GHz/9.4 T.” Journal of Magnetic Resonance 303 (June 2019): 17–27.

https://doi.org/10.1016/j.jmr.2019.04.001

We present and discuss the performance of 1H electron-nuclear double resonance (ENDOR) at 263 GHz/9.4 Tesla by employing a prototype, commercial quasi optical spectrometer. Basic instrumental features of the setup are described alongside a comprehensive characterization of the new ENDOR probe head design. The performance of three different ENDOR pulse sequences (Davies, Mims and CP-ENDOR) is evaluated using the 1H BDPA radical. A key feature of 263 GHz spectroscopy – the increase in orientiation selectivity in comparison with 94 GHz experiments – is discussed in detail. For this purpose, the resolution of 1H ENDOR spectra at 263 GHz is verified using a representative protein sample containing approximately 15 picomoles of a tyrosyl radical. Davies ENDOR spectra recorded at 5 K reveal previously obscured spectral features, which are interpreted by spectral simulations aided by DFT calculations. Our analysis shows that seven internal proton couplings are detectable for this specific radical if sufficient orientation selectivity is achieved. The results prove the fidelity of 263 GHz experiments in reporting orientation-selected 1H ENDOR spectra and demonstrate that new significant information can be uncovered in complex molecular systems, owing to the enhanced resolution combined with high absolute sensitivity and no compromise in acquisition time.

Time domain measurement of electron spin relaxation at high fields and dynamic nuclear polarization at sub-millimeter wavelengths #DNPNMR

Dubroca, Thierry, Johannes McKay, Xiaoling Wang, and Johan van Tol. “Time Domain Measurement of Electron Spin Relaxation at High Fields and Dynamic Nuclear Polarization at Sub-Millimeter Wavelengths.” In 2017 IEEE MTT-S International Microwave Symposium (IMS), 1400–1403. Honololu, HI, USA: IEEE, 2017.

https://doi.org/10.1109/MWSYM.2017.8058878

We describe a 395 GHz pulsed electron paramagnetic resonance (EPR) setup, and initial results of relaxation measurements and cw EPR at these frequencies in samples used for liquidand solid-state nuclear magnetic resonance enhanced by dynamic nuclear polarization (DNP). Depending on the amount of spin –orbit coupling, the spin lattice relaxation becomes significantly faster at higher fields and frequencies, which has consequences for some DNP applications at high fields and frequencies. We will discuss the requirements for (sub)millimeter-wave sources and components for DNP and pulsed EPR at even higher frequencies and fields, as even higher magnetic fields will become available in the near future.

Have a question?

If you have questions about our instrumentation or how we can help you, please contact us.