title: Effect of positional isomerism and vanadium substitution on51V magic angle spinning NMR Spectra Of Wells-Dawson polyoxotungstates.
abstract: We examined the positional isomerism and vanadium substitution on the51V magic angle spinning NMR spectra of potassium salts of vanadium-substituted polyoxotungstates of the Wells-Dawson series. NMR parameters of this class of catalytically active polyoxotungstates effect of are reported. Multiple species, indicative of differences in the local environment at the substitution sites, are observed in solid-state NMR spectra of the di- and tri- substituted complexes in contrast to solution NMR spectra, where single average chemical shift was observed. The quadrupolar and chemical shift anisotropy parameters depend strongly on the position and the degree of the vanadium substitution into the oxoanion core establishing51V SATRAS NMR spectroscopy as a sensitive probe of the local electronic environment in these catalytically active solids.
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA.
authors.forename: Rupal
authors.initials: R
authors.lastname: Gupta
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA.
authors.forename: Wenlin
authors.initials: W
authors.lastname: Huang
authors.affiliation: Department of Chemistry, City University of New York, Hunter College, 695 Park Avenue, New York 10021, USA; Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York 10016, USA. Electronic address: lfrances@hunter.cuny.edu.
authors.forename: Lynn C
authors.initials: LC
authors.lastname: Francesconi
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA. Electronic address: tpolenov@udel.edu.
authors.forename: Tatyana
authors.initials: T
authors.lastname: Polenova
mesh_terms: D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008968:Molecular Conformation; D017973:Tungsten Compounds / Q000737:chemistry*; D014639:Vanadium / Q000737:chemistry*
chemical_list: D017973:Tungsten Compounds; D014639:Vanadium
keywords: (51)V; Chemical shift anisotropy; Magic angle spinning; Oxotungstate; POM; Polyoxoanion; Polyoxometalate; Quadrupolar coupling; Solid-state NMR; Wells-Dawson