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Updated: Feb 16, 2026
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Structure cristalline et analyses thermique et de surface Hirshfeld du diperchlorate de
Hammouda Chebbi1,2, Abdessalem Boumakhla1, Mohamed Faouzi Zid1
1Université de Tunis El Manar, Faculté des Sciences de Tunis, Laboratoire de Matériaux, Cristallochimie et Thermodynamique Appliquée, 2092 El Manar II, Tunis, Tunisia.
Abstract:
The synthesis of 4-aza-niumyl-2,2,6,6-tetra-methyl-piperidin-1-ium diperchlorate, C9H22N22+·2ClO4-, was carried out from an aqueous reaction of perchloric acid with 4-amino-2,2,6,6-tetra-methyl-piperidine. This compound was characterized by TGA-DSC analysis and single-crystal X-ray diffraction. The piperidine ring of the dication adopts a chair conformation and the orientation of the C-NH3 bond is equatorial. One of the two crystallographically independent perchlorate anions exhibits disorder [occupancies 0.625 (7) and 0.375 (7)]. The crystal packing is constituted by a succession of mixed layers parallel to the (-102) plane, made up of C9H22N22+ dications and ClO4- anions. These ions are linked by normal and bifurcated N-H⋯O hydrogen bonds with R44(12) graph-set motifs, generating a two-dimensional network. The inter-molecular inter-actions in the crystal structure were qu-anti-fied and analysed using Hirshfeld surface analysis.
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