Structural Phase Transition Peculiarities in Ion-Molecular Perchlorate Crystals

Resumo

Molecular relaxation processes are inspected in potassium and cesium perchlorates (KClO₄ and CsClO₄, respectively) via Raman spectroscopy. A first-order phase transition in KClO₄ and CsClO₄ crystal perchlorates is found to be extended. A pretransition region is also detected in KClO₄ and CsClO₄ systems, wherein the vibrational band widths are shown to remain almost unchanged, but abruptly increase at the phase transition point.