In dynamic nuclear polarization (DNP) experiments, the compound is driven out-of-equilibrium by the microwave (MW) irradiation of the radical electron spins. Their stationary state has been recently probed via electron double resonance (ELDOR) techniques showing, at low temperature, a broad depolarization of the electron paramagnetic resonance (EPR) spectrum under microwave irradiation. In this theoretical manuscript, we develop a numerical method to compute exactly the EPR spectrum in the presence of dipolar interactions. Our results reproduce the observed broad depolarisation and provide a microscopic justification for the spectral diffusion mechanism. We show the validity of the spin-temperature approach for typical radical concentration used in dissolution DNP protocols. In particular once the interactions are properly taken into account, the spin-temperature is consistent with the non-monotonic behavior of the EPR spectrum with a wide minimum around the irradiated frequency.
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Phenylazide Hybrid-Silica - Polarization Platform for Dynamic Nuclear Polarization at Cryogenic Temperatures #DNPNMR
From The DNP-NMR Blog:
Phenylazide Hybrid-Silica - Polarization Platform for Dynamic Nuclear Polarization at Cryogenic Temperatures #DNPNMR
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Grüning, W.R., et al., Phenylazide Hybrid-Silica - Polarization Platform for Dynamic Nuclear Polarization at Cryogenic Temperatures. Helvetica Chimica Acta, 2016: p. n/a-n/a.
http://dx.doi.org/10.1002/hlca.201600122
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11-19-2016 08:35 PM
Gd(iii) and Mn(ii) complexes for dynamic nuclear polarization: small molecular chelate polarizing agents and applications with site-directed spin labeling of proteins #DNPNMR
From The DNP-NMR Blog:
Gd(iii) and Mn(ii) complexes for dynamic nuclear polarization: small molecular chelate polarizing agents and applications with site-directed spin labeling of proteins #DNPNMR
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Kaushik, M., et al., Gd(iii) and Mn(ii) complexes for dynamic nuclear polarization: small molecular chelate polarizing agents and applications with site-directed spin labeling of proteins. Phys Chem Chem Phys, 2016. 18(39): p. 27205-27218.
https://www.ncbi.nlm.nih.gov/pubmed/27545112
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11-19-2016 08:35 PM
Hyperpolarization of Frozen Hydrocarbon Gases by Dynamic Nuclear Polarization at 1.2 K #DNPNMR
From The DNP-NMR Blog:
Hyperpolarization of Frozen Hydrocarbon Gases by Dynamic Nuclear Polarization at 1.2 K #DNPNMR
Vuichoud, B., et al., Hyperpolarization of Frozen Hydrocarbon Gases by Dynamic Nuclear Polarization at 1.2 K. J Phys Chem Lett, 2016. 7(16): p. 3235-9.
https://www.ncbi.nlm.nih.gov/pubmed/27483034
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09-22-2016 10:41 PM
Molecular Rationale for Improved Dynamic Nuclear Polarization of Biomembranes #DNPNMR
From The DNP-NMR Blog:
Molecular Rationale for Improved Dynamic Nuclear Polarization of Biomembranes #DNPNMR
Smith, A.N., et al., Molecular Rationale for Improved Dynamic Nuclear Polarization of Biomembranes. J Phys Chem B, 2016. 120(32): p. 7880-8.
https://www.ncbi.nlm.nih.gov/pubmed/27434371
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09-22-2016 10:41 PM
Dynamic nuclear polarization at 40 kHz magic angle spinning #DNPNMR
From The DNP-NMR Blog:
Dynamic nuclear polarization at 40 kHz magic angle spinning #DNPNMR
Chaudhari, S.R., et al., Dynamic nuclear polarization at 40 kHz magic angle spinning. Phys Chem Chem Phys, 2016. 18(15): p. 10616-22.
http://www.ncbi.nlm.nih.gov/pubmed/27035630
Dynamic nuclear polarization of biocompatible (13)C-enriched carbonates for in vivo pH imaging #DNPNMR
From The DNP-NMR Blog:
Dynamic nuclear polarization of biocompatible (13)C-enriched carbonates for in vivo pH imaging #DNPNMR
Korenchan, D.E., et al., Dynamic nuclear polarization of biocompatible (13)C-enriched carbonates for in vivo pH imaging. Chem Commun (Camb), 2016. 52(14): p. 3030-3.
http://www.ncbi.nlm.nih.gov/pubmed/26792559
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06-02-2016 02:11 AM
Essentials of Dynamic Nuclear Polarization #DNPNMR
From The DNP-NMR Blog:
Essentials of Dynamic Nuclear Polarization #DNPNMR
Dear Colleague,
It is my pleasure to announce that a limited edition of
`Essentials of Dynamic Nuclear Polarization'
is now available at the UK branch of Amazon: www.amazon.co.uk
Evidence of spin-temperature in dynamic nuclear polarization: an exact computation of the EPR spectrum #DNPNMR
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