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Rational design of dinitroxide biradicals for efficient cross-effect dynamic nuclear polarization.

ABSTRACT: A series of 37 dinitroxide biradicals have been prepared and their performance studied as polarizing agents in cross-effect DNP NMR experiments at 9.4 T and 100 K in 1,1,2,2-tetrachloroethane (TCE). We observe that in this regime the DNP performance is strongly correlated with the substituents on the polarizing agents, and electron and nuclear spin relaxation times, with longer relaxation times leading to better enhancements. We also observe that deuteration of the radicals generally leads to better DNP enhancement but with longer build-up time. One of the new radicals introduced here provides the best performance obtained so far under these conditions.

SUBMITTER: Kubicki DJ

PROVIDER: S-EPMC5952883 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Rational design of dinitroxide biradicals for efficient cross-effect dynamic nuclear polarization.

Kubicki Dominik J DJ Casano Gilles G Schwarzwälder Martin M Abel Sébastien S Sauvée Claire C Ganesan Karthikeyan K Yulikov Maxim M Rossini Aaron J AJ Jeschke Gunnar G Copéret Christophe C Lesage Anne A Tordo Paul P Ouari Olivier O Emsley Lyndon L

Chemical science 20151013 1

A series of 37 dinitroxide biradicals have been prepared and their performance studied as polarizing agents in cross-effect DNP NMR experiments at 9.4 T and 100 K in 1,1,2,2-tetrachloroethane (TCE). We observe that in this regime the DNP performance is strongly correlated with the substituents on the polarizing agents, and electron and nuclear spin relaxation times, with longer relaxation times leading to better enhancements. We also observe that deuteration of the radicals generally leads to be ...[more]

PMID: 29896347

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