title: An unprecedented tetranuclear niobium aqua ion with a capping mu4-sulfido ligand.
abstract: The aqueous solution chemistry of niobium is rather unexplored, and well characterized aqua complexes are scarce. In this work, a new niobium aqua ion is obtained upon treatment of Zn-reduced ethanolic solutions of NbCl5 with HCl in the presence of a sulfide source. The red aqua ion, obtained upon cation-exchange chromatography, forms readily the thiocyanate complex which has been crystallized as Cs(4.26)Na(1.74)[Nb4SO5(NCS)10] . 0.33H2O. X-ray crystallography revealed an unprecedented metal-metal bonded tetranuclear Nb4(mu4-S)(mu2-O)5(4+) core with a capping mu4-S ligand.
authors.affiliation: Department of Chemistry, Technical University of Denmark, Kemitorvet, Building 207, 2800 Kgs. Lyngby, Denmark. obl@kemi.dtu.dk
authors.forename: Bee-Lean
authors.initials: BL
authors.lastname: Ooi
authors.forename: Inger
authors.initials: I
authors.lastname: Søtofte
authors.forename: Maja F
authors.initials: MF
authors.lastname: Bendtsen
authors.forename: Astrid
authors.initials: A
authors.lastname: Munch
authors.forename: Loa C
authors.initials: LC
authors.lastname: Nielsen
authors.forename: Jonas
authors.initials: J
authors.lastname: Henriksen