Production of complex rubidium and cesium hydrogen sulfate-phosphates.

The solubility in the CsHPO-CsHSO-HO system at different temperatures (25, 50, and 75°C) is studied and the phase equilibria in the RbH(SO)-RbHPO-HO system under isothermal conditions (at 25°C) are analyzed. The temperature and concentration conditions for forming Rb(HSO)(HPO), Rb(HSO)(HPO), Cs(HSO)(HPO), Cs(HSO)(HPO), Cs(HSO)(HPO), and CsH(HSO)(HPO) compounds (the latter has been obtained for the first time) are determined. The conditions for growing large single crystals of complex acid rubidium and cesium salts are found. [ABSTRACT FROM AUTHOR]