title: EXAFS study of glass transition in K1-x(NH4)xI.
abstract: The iodine K-edge EXAFS study of K1-x(NH4)xI mixed crystals was performed to clarify the local structure of the dipole glass associated with the random reorientational freezing of ammnonium ions. The pair-distribution function of the nearest iodine-iodine ions is strongly reduced with increasing ammonium concentration. The reduction originates in the local distortion of lattice induced by the short-range antiferroelectric order of ammonium ions. We discuss the relationship between the reorientational freezing of ammonium ions and the local distortion of lattice in comparison with the results of X-ray diffraction measurements.
authors.affiliation: Advanced Research Center of Science and School of Science, Kwansei-Gakuin University, Sanda, Hyogo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yagi
authors.forename: K
authors.initials: K
authors.lastname: Sakaue
authors.forename: H
authors.initials: H
authors.lastname: Terauchi