title: Potassium gallium hydrogenphosphate fluoride, K(2)Ga[H(HPO(4))(2)]F(2).
abstract: Hydrothermally synthesized dipotassium gallium {hydrogen bis[hydrogenphosphate(V)]} difluoride, K(2)Ga[H(HPO(4))(2)]F(2), is isotypic with K(2)Fe[H(HPO(4))(2)]F(2). The main features of the structure are ([Ga{H(HPO(4))(2)}F(2)](2-))(n) columns consisting of centrosymmetric Ga(F(2)O(4)) octahedra [average Ga-O = 1.966 (3) Angstrom and Ga-F = 1.9076 (6) Angstrom] stacked above two HPO(4) tetrahedra [average P-O = 1.54 (2) Angstrom] sharing two O-atom vertices. The charge-balancing seven-coordinate K(+) cations [average K-O,F = 2.76 (2) Angstrom] lie in the intercolumn space, stabilizing a three-dimensional structure. Strong [O...O = 2.4184 (11) Angstrom] and medium [O...F = 2.6151 (10) Angstrom] hydrogen bonds further reinforce the connections between adjacent columns.
authors.affiliation: Laboratoire de Cristallographie, Ecole Polytechnique Fédérale de Lausanne, Le Cubotron, Dorigny, CH-1015 Lausanne, Switzerland. andrey.filaretov@epfl.ch
authors.forename: Andrey
authors.initials: A
authors.lastname: Filaretov
authors.forename: Kurt J
authors.initials: KJ
authors.lastname: Schenk
authors.forename: Dmitriy
authors.initials: D
authors.lastname: Rusakov
authors.forename: Gervais
authors.initials: G
authors.lastname: Chapuis