Ferroelastic Phase Transitions in Mixed KSc(MoO₄)₂ Based Trigonal Double Molybdates

Abstract

Electron paramagnetic resonance method of Cr³⁺ ions was used in order to investigate disorder and structural phase transitions in mixed double trigonal molybdates K_1–xRb_xSc(MoO₄)₂ with x = 0.03, 0.1 and 0.2. The computer reconstruction of the EPR spectra allows to get information about the substitutional disorder induced by Rb⁺ ions in the neighbourhood of the Cr³⁺ probe. Through temperature EPR and polarized-ligth microscopy studies ferroelastic phase transitions in the mixed crystals have been found.

Keywords:

• Phase transition
• electron paramagnetic resonance
• trigonal double molybdates
• ferroelastic domain structure
• inhomogeneous broadening