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.
The enhancement of the nuclear spin polarization generated by dynamic nuclear polarization depends on two competing processes: the perturbation of the thermal equilibrium by the applied microwave field and the tendency of relaxation processes to re-establish the thermal state. Hence, it is important to correctly incorporate relaxation processes in the theoretical description of dynamic nuclear polarization to obtain meaningful simulations. A difficulty arises in the choice of the correct interaction frame when building an appropriate relaxation superoperator. In the Zeeman frame, the rate constants introduced to define longitudinal and transverse relaxation can become mixed if the non-secular part of the hyperfine interaction between an electron in a paramagnetic centre and the nuclear spins is strong. Deriving the relaxation superoperator in the interaction frame that is defined by the eigenbasis of the stationary Hamiltonian eliminates this issue. However, when using this strategy, not all the non-secular terms arising in a relaxation model based on local magnetic field fluctuations are taken properly into account if dipolar interactions between nuclear spins dominate over hyperfine interactions. An analytical treatment of this problem is presented that is corroborated by a set of numerical simulations focussing on the case of solid effect dynamic nuclear polarization. The advantage and possible errors arising when using either of the two strategies are briefly summarised and discussed.
Quantitative cw Overhauser effect dynamic nuclear polarization for the analysis of local water dynamics
From The DNP-NMR Blog:
Quantitative cw Overhauser effect dynamic nuclear polarization for the analysis of local water dynamics
Franck, J.M., et al., Quantitative cw Overhauser effect dynamic nuclear polarization for the analysis of local water dynamics. Prog Nucl Magn Reson Spectrosc, 2013. 74(0): p. 33-56.
http://www.ncbi.nlm.nih.gov/pubmed/24083461
Dynamic Nuclear Polarization Enhanced NMR in the Solid-State
From The DNP-NMR Blog:
Dynamic Nuclear Polarization Enhanced NMR in the Solid-State
Akbey, Ü., et al., Dynamic Nuclear Polarization Enhanced NMR in the Solid-State. 2013, Springer Berlin Heidelberg. p. 1-48.
http://dx.doi.org/10.1007/128_2013_436
nmrlearner
News from NMR blogs
0
08-26-2013 08:46 PM
[NMR paper] Dynamic Nuclear Polarization Enhanced NMR in the Solid-State.
Dynamic Nuclear Polarization Enhanced NMR in the Solid-State.
Dynamic Nuclear Polarization Enhanced NMR in the Solid-State.
Top Curr Chem. 2013 Jul 7;
Authors: Akbey U, Franks WT, Linden A, Rydmark MO, Lange S, Oschkinat H
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is one of the most commonly used spectroscopic techniques to obtain information on the structure and dynamics of biological and chemical materials. A variety of samples can be studied including solutions, crystalline solids, powders and hydrated protein...
nmrlearner
Journal club
0
07-09-2013 02:47 PM
Solid state nuclear magnetic resonance with magic-angle spinning and dynamic nuclear polarization below 25K
Solid state nuclear magnetic resonance with magic-angle spinning and dynamic nuclear polarization below 25K
January 2013
Publication year: 2013
Source:Journal of Magnetic Resonance, Volume 226</br>
</br>
We describe an apparatus for solid state nuclear magnetic resonance (NMR) with dynamic nuclear polarization (DNP) and magic-angle spinning (MAS) at 20–25K and 9.4Tesla. The MAS NMR probe uses helium to cool the sample space and nitrogen gas for MAS drive and bearings, as described earlier , but also includes a corrugated waveguide for transmission of microwaves from...
nmrlearner
Journal club
0
12-15-2012 09:51 AM
Dynamic nuclear polarization experiments at 14.1 T for solid-state NMR.
Dynamic nuclear polarization experiments at 14.1 T for solid-state NMR.
Related Articles Dynamic nuclear polarization experiments at 14.1 T for solid-state NMR.
Phys Chem Chem Phys. 2010 Jun 14;12(22):5799-803
Authors: Matsuki Y, Takahashi H, Ueda K, Idehara T, Ogawa I, Toda M, Akutsu H, Fujiwara T
Instrumentation for high-field dynamic nuclear polarization (DNP) at 14.1 T was developed to enhance the nuclear polarization for NMR of solids. The gyrotron generated 394.5 GHz submillimeter (sub-mm) wave with a power of 40 W in the second harmonic...
The Role of the Interaction Frame in the Theoretical Description of Solid Effect Dynamic Nuclear Polarization
Linear Mode
