title: Dirubidium fluorotrioxophosphate, Rb2PO3F, at 290 and 130 K, and dicaesium fluorotrioxophosphate, Cs2PO3F, at 240 and 100 K.
abstract: The structure of Rb2PO3F was determined at 290 and 130 K, while that of Cs2PO3F was determined at 240 and 100 K. Both compounds belong to the beta-K2SO4 family. The structure analysis did not reveal signs of a phase transition in either compound. Crystal chemical considerations do not favour the presence of a phase transition in either Rb2PO3F or Cs2PO3F. However, glass-like phase transitions were observed by differential scanning calorimetry in slightly humid samples at 175 and 177 K for Rb2PO3F and Cs2PO3F, respectively, but were not observed in well dried samples. The bond distances are normal and Cs2PO3F is twinned.
authors.affiliation: Institute of Physics of the Czech Academy of Sciences, Na Slovance 2, 182 21 Praha 8, Czech Republic. fabry@fzu.cz
authors.forename: Jan
authors.initials: J
authors.lastname: Fábry
authors.forename: Michal
authors.initials: M
authors.lastname: Dusek
authors.forename: Karla
authors.initials: K
authors.lastname: Fejfarová
authors.forename: Radmila
authors.initials: R
authors.lastname: Krupková
authors.forename: Premysl
authors.initials: P
authors.lastname: Vanek
authors.forename: Ivana
authors.initials: I
authors.lastname: Císarová