title: Solvent suppression in DNP enhanced solid state NMR.
abstract: We show how DNP enhanced solid-state NMR spectra can be dramatically simplified by suppression of solvent signals. This is achieved by (i) exploiting the paramagnetic relaxation enhancement of solvent signals relative to materials substrates, or (ii) by using short cross-polarization contact times to transfer hyperpolarization to only directly bonded carbon-13 nuclei in frozen solutions. The methods are evaluated for organic microcrystals, surfaces and frozen solutions. We show how this allows for the acquisition of high-resolution DNP enhanced proton-proton correlation experiments to measure inter-nuclear proximities in an organic solid.
authors.affiliation: Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Jayasubba Reddy
authors.initials: JR
authors.lastname: Yarava
authors.affiliation: Centre de RMN a Trés Hauts Champs, Institut de Sciences Analytiques (CNRS/ENS Lyon/UCB Lyon 1), Université de Lyon, 69100 Villeurbanne, France.
authors.forename: Sachin Rama
authors.initials: SR
authors.lastname: Chaudhari
authors.affiliation: Department of Chemistry, Iowa State University, Ames, IA, USA.
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Rossini
authors.affiliation: Centre de RMN a Trés Hauts Champs, Institut de Sciences Analytiques (CNRS/ENS Lyon/UCB Lyon 1), Université de Lyon, 69100 Villeurbanne, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Lesage
authors.affiliation: Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland. Electronic address: lyndon.emsley@epfl.ch.
authors.forename: Lyndon
authors.initials: L
authors.lastname: Emsley
keywords: DNP; Paramagnetic relaxation enhancement (PRE); Relaxation filters; Solid-state NMR; Solvent suppression