Here, we present an integrated experimental and theoretical study of 1H dynamic nuclear polarization (DNP) of a frozen aqueous glass containing free radicals at 7 T, under static conditions and at temperatures ranging between 4 and 20 K. The DNP studies were performed with a home-built 200 GHz quasi-optics microwave bridge, powered by a tunable solid-state diode source. DNP using monochromatic and continuous wave (cw) irradiation applied to the electron paramagnetic resonance (EPR) spectrum of the radicals induces the transfer of polarization from the electron spins to the surrounding nuclei of the solvent and solutes in the frozen aqueous glass. In our systematic experimental study, the DNP enhanced 1H signals are monitored as a function of microwave frequency, microwave power, radical concentration, and temperature, and are interpreted with the help of electron spin-lattice relaxation times, experimental MW irradiation parameters, and the electron spectral diffusion (eSD) model introduced previously. This comprehensive experimental DNP study with mono-nitroxide radical spin probes was accompanied with theoretical calculations. Our results consistently demonstrate that eSD effects can be significant at 7 T under static DNP conditions, and can be systematically modulated by experimental conditions.
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Temperature dependence of cross-effect dynamic nuclear polarization in rotating solids: advantages of elevated temperatures #DNPNMR
From The DNP-NMR Blog:
Temperature dependence of cross-effect dynamic nuclear polarization in rotating solids: advantages of elevated temperatures #DNPNMR
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Geiger, M.A., et al., Temperature dependence of cross-effect dynamic nuclear polarization in rotating solids: advantages of elevated temperatures. Phys. Chem. Chem. Phys., 2016. 18(44): p. 30696-30704.
https://www.ncbi.nlm.nih.gov/pubmed/27791210
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01-25-2017 11:13 PM
Rational design of dinitroxide biradicals for efficient cross-effect dynamic nuclear polarization #DNPNMR
From The DNP-NMR Blog:
Rational design of dinitroxide biradicals for efficient cross-effect dynamic nuclear polarization #DNPNMR
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Kubicki, D.J., et al., Rational design of dinitroxide biradicals for efficient cross-effect dynamic nuclear polarization. Chem. Sci., 2016. 7(1): p. 550-558.
http://dx.doi.org/10.1039/C5SC02921J
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01-06-2017 07:43 PM
Rational design of dinitroxide biradicals for efficient cross-effect dynamic nuclear polarization #DNPNMR
From The DNP-NMR Blog:
Rational design of dinitroxide biradicals for efficient cross-effect dynamic nuclear polarization #DNPNMR
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Kubicki, D.J., et al., Rational design of dinitroxide biradicals for efficient cross-effect dynamic nuclear polarization. Chem. Sci., 2016. 7(1): p. 550-558.
http://dx.doi.org/10.1039/C5SC02921J
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12-19-2016 03:37 AM
Correction: Theory of solid effect and cross effect dynamic nuclear polarization with half-integer high-spin metal polarizing agents in rotating solids #DNPNMR
From The DNP-NMR Blog:
Correction: Theory of solid effect and cross effect dynamic nuclear polarization with half-integer high-spin metal polarizing agents in rotating solids #DNPNMR
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Corzilius, B., Correction: Theory of solid effect and cross effect dynamic nuclear polarization with half-integer high-spin metal polarizing agents in rotating solids. Phys. Chem. Chem. Phys., 2016. 18(42): p. 29643-29643.
http://dx.doi.org/10.1039/C6CP90249A
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12-17-2016 07:18 AM
Theory of solid effect and cross effect dynamic nuclear polarization with half-integer high-spin metal polarizing agents in rotating solids #DNPNMR
From The DNP-NMR Blog:
Theory of solid effect and cross effect dynamic nuclear polarization with half-integer high-spin metal polarizing agents in rotating solids #DNPNMR
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Corzilius, B., Theory of solid effect and cross effect dynamic nuclear polarization with half-integer high-spin metal polarizing agents in rotating solids. Phys. Chem. Chem. Phys., 2016. 18(39): p. 27190-27204.
http://dx.doi.org/10.1039/C6CP04621E
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11-21-2016 11:02 PM
Static (1)H dynamic nuclear polarization with the biradical TOTAPOL: a transition between the solid effect and the cross effect
From The DNP-NMR Blog:
Static (1)H dynamic nuclear polarization with the biradical TOTAPOL: a transition between the solid effect and the cross effect
Shimon, D., et al., Static (1)H dynamic nuclear polarization with the biradical TOTAPOL: a transition between the solid effect and the cross effect. Phys Chem Chem Phys, 2014. 16(14): p. 6687-99.
http://www.ncbi.nlm.nih.gov/pubmed/24585094
Effect of electron spectral diffusion on static dynamic nuclear polarization at 7 Tesla #DNPNMR
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