title: Polyoxometalate-supported Y- and YbIII-hydroxo/oxo clusters from carbonate-assisted hydrolysis.
abstract: Carbonate-assisted hydrolysis of Y or Yb(III) ions in the presence of the trivacant Wells-Dawson polyoxoanion, alpha-[P(2)W(15)O(56)](12-), produced two polyoxometalate-supported Y- or Yb(III)-hydroxo/oxo clusters, which have been characterized by single-crystal X-ray structure determination. The structure of the Y complex consists of a distorted Y(4)(OH)(4) cubane cluster encapsulated by two lacunary alpha-[P(2)W(15)O(56)](12-) units, while the Yb cluster features a hexametallic core centered around a mu(6)-oxo atom with each Yb(3)(III) triangular face capped by an oxo or a hydroxo group. Magnetization measurements of the ytterbium(III) derivative suggested that intermolecular dipolar exchange is present at low temperatures (below 15 K). Despite its absence in the structures themselves, control experiments show that carbonate not only functions in the hydrolysis, it also influences the structure of the complexes by complexation to yttrium and the f-block elements.
authors.affiliation: Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, GA 30322, USA.
authors.forename: Xikui
authors.initials: X
authors.lastname: Fang
authors.forename: Travis M
authors.initials: TM
authors.lastname: Anderson
authors.forename: Cristiano
authors.initials: C
authors.lastname: Benelli
authors.forename: Craig L
authors.initials: CL
authors.lastname: Hill