title: High-pressure synthesis and structure determination of K6(SeO4)(SeO5), the first potassium orthoselenate(VI).
abstract: We report on the first synthesis of a potassium orthoselenate(VI), K6(SeO4)(SeO5), and the structure determination from synchrotron powder diffraction data. The title compound crystallizes in the tetragonal space group P41212 with a = 8.1259(1) A, c = 17.4953(2) A, V = 1155.21(2) A3, and Z = 4. Selenium displays two different complex anions, tetrahedral SeO42- and trigonal-bipyramidal SeO54-. When the formula is reduced to A3B, the spatial arrangement of the constituting building units can be derived from the Li3Bi type of structure.
authors.affiliation: Max-Planck Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany.
authors.forename: Denis
authors.initials: D
authors.lastname: Orosel
authors.forename: Robert
authors.initials: R
authors.lastname: Dinnebier
authors.forename: Martin
authors.initials: M
authors.lastname: Jansen