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Updated: Feb 25, 2026

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
The phase transition of rubidium hydrogen carbonate, RbHCO3
Carla Larvor1, Berthold Stöger2
1Département Mesures Physique, Institut Universitaire Téchnologique de Bordeaux, 15 Rue de Naudet, 33175 Gradignan, France.
Abstract:
Rubidium hydrogen carbonate, RbHCO3, features an order/disorder phase transition at TC = 245 K from the high-temperature (HT) disordered C2/m modification to the low-temperature (LT) C-1 modification. The crystal structures are characterized by [HCO3]22- pairs of hydrogen carbonate groups connected by strong hydrogen bonding. The [HCO3]22- pairs are connected by Rb+ cations into a three-dimensional network. In HT-RbHCO3, the hydrogen atom is disordered. In LT-RbHCO3, ordering of the hydrogen atom leads to a translation-engleiche symmetry reduction of index 2. The lost reflections and rotations are retained as twin operations.
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