Thermal, spectral and microscopic studies of water-rich hydrate of the type Mg2KH(PO4)2·15H2O. Thermal transformations

• Mg2KH(PO4)2·15H2O is rare example of water-rich salt with H(PO4)2 symmetric dimers.
• First thermal, spectral and microscopic examination of Mg2KH(PO4)2·15H2O.
• IR spectra of Mg2KH(PO4)2·15H2O are reported and analyzed.
• New insights on the thermal behavior of Mg2KH(PO4)2·15H2O are obtained.
• Complex phase transformations take place between 400 and 1000 °C.

A little known compound of the type Mg2KH(PO4)2·15H2O which is a rare example of highly hydrated salt containing H(PO4)2 symmetric dimers has been studied with a particular focus on its spectroscopic and thermal features. The infrared spectra have been recorded at room and liquid nitrogen temperatures and assignment of the observed vibrational bands has been proposed. The thermal behavior of Mg2KH(PO4)2·15H2O has been examined by simultaneous TG/DTA/mass spectrometry technique in a broad temperature interval up to 1000 °C. New insights on the processes of thermal decomposition as well as on the solid state transformations up to 1000 °C have been obtained by combination of the TG/DTA/MS analyses with IR spectroscopic and XRD studies.

Figure optionsDownload as PowerPoint slide