Phase Transitions in Trirubidium Hydrogen Diselenate Rb₃H(SeO₄)₂

Abstract

It has been shown that Rb 3 H(SeO 4 ) 2 undergoes successive phase transitions at 178°C and 302°C by the DTA analysis. The dielectric behavior is quite similar to that in Rb 3 H(SO 4 ) 2 in a range from room temperature to liquid nitrogen temperature. In Rb 3 H(XO 4 ) 2 (X=S, Se) system a corresponding relation between the phases can be recognized in contrast to (NH 4 ) 3 H(XO 4 ) 2 system.