The phase transition of rubidium hydrogen carbonate, RbHCO₃.

ABSTRACT: Rubidium hydrogen carbonate, RbHCO₃, features an order/disorder phase transition at T_C = 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]₂^2- pairs of hydrogen carbonate groups connected by strong hydrogen bonding. The [HCO₃]₂^2- 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.

SUBMITTER: Larvor C 

PROVIDER: S-EPMC5499272 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature