title: Measurement of interfluorine distances in solids.
abstract: (19)F homonuclear dipolar recoupling methods were used to measure internuclear distances ranging from 5 to 12 A in fluorinated organic compounds in the solid state. Magic-angle-spinning-based high-resolution techniques were utilized. Trifluoromethyl and aromatic fluorine groups were separated by rigid aromatic spacers; these compounds were diluted into nonfluorinated host molecule matrices to give isolated homonuclear spin pairs with known internuclear distances. Radiofrequency-driven recoupling (RFDR) was used to elicit magnetization exchange between the spin pairs in 1D and 2D experiments. Simulation of the exchange was accomplished using a Monte Carlo-type algorithm to search the parameter space. These methods allow the determination of distances with an accuracy of 1 A at shorter distances and 2 A at longer distances, with the assumption of no prior knowledge of T(2)(ZQ).
authors.affiliation: Department of Chemistry, Columbia University, New York, New York 10027, USA.
authors.forename: M L
authors.initials: ML
authors.lastname: Gilchrist
authors.forename: K
authors.initials: K
authors.lastname: Monde
authors.forename: Y
authors.initials: Y
authors.lastname: Tomita
authors.forename: T
authors.initials: T
authors.lastname: Iwashita
authors.forename: K
authors.initials: K
authors.lastname: Nakanishi
authors.forename: A E
authors.initials: AE
authors.lastname: McDermott
mesh_terms: D005461:Fluorine / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008433:Mathematics; D055585:Physical Phenomena; D010825:Physics
chemical_list: D005461:Fluorine