Filibian, M., et al., The role of the glassy dynamics and thermal mixing in the dynamic nuclear polarization and relaxation mechanisms of pyruvic acid. Phys Chem Chem Phys, 2014. 16(48): p. 27025-36.
The temperature dependence of (1)H and (13)C nuclear spin-lattice relaxation rate 1/T1 has been studied in the 1.6-4.2 K temperature range in pure pyruvic acid and in pyruvic acid containing trityl radicals at a concentration of 15 mM. The temperature dependence of 1/T1 is found to follow a quadratic power law for both nuclei in the two samples. Remarkably the same temperature dependence is displayed also by the electron spin-lattice relaxation rate 1/T1e in the sample containing radicals. These results are explained by considering the effect of the structural dynamics on the relaxation rates in pyruvic acid. Dynamic nuclear polarization experiments show that below 4 K the (13)C build up rate scales with 1/T1e, in analogy to (13)C 1/T1 and consistently with a thermal mixing scenario where all the electrons are collectively involved in the dynamic nuclear polarization process and the nuclear spin reservoir is in good thermal contact with the electron spin system.
[NMR paper] Mechanisms of dynamic nuclear polarization in insulating solids
Mechanisms of dynamic nuclear polarization in insulating solids
Publication date: April 2015
Source:Journal of Magnetic Resonance, Volume 253</br>
Author(s): T.V. Can , Q.Z. Ni , R.G. Griffin</br>
Dynamic nuclear polarization (DNP) is a technique used to enhance signal intensities in NMR experiments by transferring the high polarization of electrons to their surrounding nuclei. The past decade has witnessed a renaissance in the development of DNP, especially at high magnetic fields, and its application in several areas including biophysics, chemistry, structural...
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03-22-2015 06:36 PM
Dynamic nuclear polarization of a glassy matrix prepared by solid state mechanochemical amorphization of crystalline substances
From The DNP-NMR Blog:
Dynamic nuclear polarization of a glassy matrix prepared by solid state mechanochemical amorphization of crystalline substances
This is a very interesting article describing the preparation of a sample for DNP by co-milling the analyte with the polarizing substrate. For a long time it was thought that just mechanically mixing the polarizing agent with the analyte will not result in a sample that is useful for DNP because the radical has to be mixed at an atomic level. Clearly this article demonstrate that this is not necessary. This will open up DNP to be used...
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02-09-2015 07:49 PM
Dynamic nuclear polarization and Hanle effect in (In,Ga)As/GaAs quantum dots. Role of nuclear spin fluctuations
From The DNP-NMR Blog:
Dynamic nuclear polarization and Hanle effect in (In,Ga)As/GaAs quantum dots. Role of nuclear spin fluctuations
Gerlovin, I.Y., et al., Dynamic nuclear polarization and Hanle effect in (In,Ga)As/GaAs quantum dots. Role of nuclear spin fluctuations. AIP Conference Proceedings, 2013. 1566(1): p. 319-320.
http://scitation.aip.org/content/aip/proceeding/aipcp/10.1063/1.4848414
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12-06-2014 04:54 AM
Dynamic nuclear polarization and Hanle effect in (In,Ga)As/GaAs quantum dots. Role of nuclear spin fluctuations
From The DNP-NMR Blog:
Dynamic nuclear polarization and Hanle effect in (In,Ga)As/GaAs quantum dots. Role of nuclear spin fluctuations
Gerlovin, I.Y., et al., Dynamic nuclear polarization and Hanle effect in (In,Ga)As/GaAs quantum dots. Role of nuclear spin fluctuations. AIP Conference Proceedings, 2013. 1566(1): p. 319-320.
http://scitation.aip.org/content/aip/proceeding/aipcp/10.1063/1.4848414
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11-18-2014 01:39 AM
Role of Electron Spin Dynamics on Solid-State Dynamic Nuclear Polarization Performance
From The DNP-NMR Blog:
Role of Electron Spin Dynamics on Solid-State Dynamic Nuclear Polarization Performance
Siaw, T.A., et al., Role of Electron Spin Dynamics on Solid-State Dynamic Nuclear Polarization Performance. Phys. Chem. Chem. Phys., 2014.
http://dx.doi.org/10.1039/C4CP02013H
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06-20-2014 08:14 PM
The Role of the Interaction Frame in the Theoretical Description of Solid Effect Dynamic Nuclear Polarization
From The DNP-NMR Blog:
The Role of the Interaction Frame in the Theoretical Description of Solid Effect Dynamic Nuclear Polarization
Kwiatkowski, G., A. Karabanov, and W. Köckenberger, The Role of the Interaction Frame in the Theoretical Description of Solid Effect Dynamic Nuclear Polarization. Israel Journal of Chemistry, 2014. 54(1-2): p. 184-195.
http://dx.doi.org/10.1002/ijch.201300125
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04-30-2014 02:21 PM
Dynamic nuclear polarization with photoexcited triplet electrons in a glassy matrix
From The DNP-NMR Blog:
Dynamic nuclear polarization with photoexcited triplet electrons in a glassy matrix
Tateishi, K., et al., Dynamic nuclear polarization with photoexcited triplet electrons in a glassy matrix. Angew Chem Int Ed Engl, 2013. 52(50): p. 13307-10.
http://www.ncbi.nlm.nih.gov/pubmed/24249595
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04-25-2014 10:26 PM
On Mechanisms of Dynamic Nuclear Polarization in Solids
From The DNP-NMR Blog:
On Mechanisms of Dynamic Nuclear Polarization in Solids
Thurber, K.R. and R. Tycko, On Mechanisms of Dynamic Nuclear Polarization in Solids. Israel Journal of Chemistry, 2013: p. n/a-n/a.
http://dx.doi.org/10.1002/ijch.201300116
The role of the glassy dynamics and thermal mixing in the dynamic nuclear polarization and relaxation mechanisms of pyruvic acid
Linear Mode
