6533b85cfe1ef96bd12bd419

RESEARCH PRODUCT

Relaxational dynamics at the class transition in orientational and canonical glasses investigated by dielectric spectroscopy

I. FehstRoland BöhmerS. L. HuttonAlois Loidl

subject

StereochemistryCondensed Matter PhysicsFerroelectricityAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsDielectric spectroscopychemistry.chemical_compoundDipoleBetainechemistryChemical physicsMaterials ChemistryRelaxation (physics)AntiferroelectricityPhysical and Theoretical ChemistryGlass transitionSpectroscopySolid solution

description

Abstract Measurements of the dielectric permittivity are reported for the canonical glass glycerol and for solid solutions of ferroelectric betaine phosphite and ferroelectric betaine phosphate, which can be viewed as protype systems of orientational glasses. In this latter system long range dipolar order is suppressed by the competing ferroelectric and antiferroelectric interactions and the dipolar moments freeze-in devoid of long range order. In both systems the relaxation dynamics is studied for frequencies 10−2Hz≤ν≤106Hz, close to the glass transition temperature. The relaxation dynamics is characterized according to Angell's classification scheme of strong and fragile glass-formers.

https://doi.org/10.1016/0167-7322(91)80071-b