Abstract: | ![]() Single crystals of Cs4(HSO4)3(H2PO4) are synthesized and studied for the first time. The new compound is found in the course of studies of the phase diagram of the CsHSO4–CsH2PO4–H2O triple system. Data on the atomic crystal structure of single-crystalline and powder specimens, as well as on structural phase transitions, are obtained. |