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Updated: Mar 25, 2026
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Redetermination of the crystal structure of 3,5-di-methyl-pyrazolium β-octa-molybdate tetra-hydrate
Tatiana R Amarante1, Isabel S Gonçalves1, Filipe A Almeida Paz1
1Department of Chemistry, CICECO - Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal.
Abstract:
The title compound, (C5H9N2)4[Mo8O26]·4H2O, was reported previously from a room-temperature data collection from which only the metal atoms could be refined anisotropically [FitzRoy et al. (1989 ▸). Inorg. Chim. Acta, 157, 187-194]. The current redetermination at 180 (2) K models all the non-H atoms with anisotropic displacement parameters and fully describes the supra-molecular N-H⋯O and O-H⋯O hydrogen-bonded network connecting the 3,5-di-methyl-pyrazolium cations, the water mol-ecules of crystallization and the β-octa-molybdate anion. All H atoms involved in the three-dimensional hydrogen-bonding network could be located from difference Fourier maps, with the exception of those of one disordered water mol-ecule, firstly seen in this structural report [refined over two distinct locations with site-occupancy factors of 0.65 (2) and 0.35 (2)]. The complete β-octa-molybdate anion is generated by a crystallographic inversion centre.
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