title: Crystal structure of bis-(9H-6-amino-purin-1-ium) hexa-fluorido-silicate(IV) dihydrate.
abstract: The asymmetric unit of the title compound, 2C5H6N5 (+)·SiF6 (2-)·2H2O, contains one adeninium cation, half of a hexa-fluorido-silicate anion located on an inversion centre and one lattice water mol-ecule. The adeninium cations are connected through N-H⋯N hydrogen bonds involving one H atom of the -NH2 group and the H atom of the protonated N atom of the adenine ring system, forming centrosymmetric ring motifs of the type R 2 (2)(10) and R 2 (2)(8), respectively. The overall connection of the cation leads to the formation of planar ribbons parallel to (122). In the ribbons, slipped π-π stacking inter-actions, with a centroid-to-centroid distance of 3.6938 (9) Å, an inter-planar distance of 3.455 Å and a slippage of 1.306 Å is observed. The hexa-fluorido-silicate anion and the water mol-ecule are linked through O-H⋯F hydrogen bonds [ring motif R 4 (4)(12)] into chains parallel to [100]. The cationic ribbons and anionic chains are finally connected through additional N-H⋯O, N-H⋯F and O-H⋯F hydrogen bonds into a three-dimensional network in which layers of adeninium cations and fluorido-silicate anions alternate parallel to (001).
authors: Unité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Université Mentouri-Constantine, 25000, Algeria.
authors: Ratiba
authors: R
authors: Belhouas
authors: Unité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Université Mentouri-Constantine, 25000, Algeria ; Département Sciences de la Matière, Faculté des Sciences Exactes et Sciences de la Nature et de la Vie, Université Oum El Bouaghi, Algeria.
authors: Sofiane
authors: S
authors: Bouacida
authors: Unité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Université Mentouri-Constantine, 25000, Algeria.
authors: Chaouki
authors: C
authors: Boudaren
authors: Laboratoire de Chimie de Coordination, UPR CNRS 8241, 205 route de Narbonne, 31077 Toulouse Cedex, France.
authors: Jean-Claude
authors: JC
authors: Daran
authors: Université Abdelmalek Essaadi, Faculté des Sciences, BP 2121 M'Hannech II, 93002 Tétouan, Morocco.
authors: El Hossain
authors: el H
authors: Chtoun
keywords: crystal structure; hexa­fluorido­silicate anion; hydrogen bonding; purinium cation