Phase diagram of ammonium perchlorate: Raman spectroscopic constrains at high pressures and temperatures Journal Article uri icon

DCO ID 11121/4288-4188-1889-1696-CC

is Contribution to the DCO

  • YES

year of publication

  • 2016

abstract

  • We present the pressure-temperature (PT) induced physical and chemical transformations in ammonium perchlorates (APs) up to 50 GPa and 450 °C, using diamond anvil cells and confocal micro-Raman spectroscopy, which provide new constraints for the phase diagram of AP. The results show spectral evidences for three new polymorphs (III, IV, and VI) of AP, in addition to two previously known phases (I and II), at various PT conditions with varying degrees of hydrogen bonding and lack of strong spectral evidence for previously known high-temperature cubic phase (phase V). Upon further heating, AP chemically decomposes to N2, N2O, and H2O. The present phase diagram is, therefore, in sharp contrast to the previous one, underscoring a rich polymorphism, a large stability field for solids, and a replacement of the melt with a decomposition line.

volume

  • 144

issue

  • 24