title: Abrupt boundaries of intermediate phases and space filling in oxide glasses.
abstract: Modulated differential scanning calorimetry measurements on bulk (Na(2)O)(x)(GeO(2))(1-x) glasses show a sharp reversibility window in the 14%<x<19% soda range, which correlates well with a broad global minimum in molar volumes. Raman and IR reflectance transverse- and longitudinal-optic mode frequencies exhibit anomalies between x(c)(1) = 14% (stress transition) and x(c)(2) = 19% (rigidity transition), with optical elasticity power laws confirming the nature of the transitions. Birefringence measurements dramatize the macroscopically stress-free nature of the intermediate phase in the reversibility window.
authors.affiliation: Department of Electrical and Computer Engineering, University of Cincinnati, Cincinnati, OH 45221-0030, USA.
authors.forename: K
authors.initials: K
authors.lastname: Rompicharla
authors.forename: D I
authors.initials: DI
authors.lastname: Novita
authors.forename: P
authors.initials: P
authors.lastname: Chen
authors.forename: P
authors.initials: P
authors.lastname: Boolchand
authors.forename: M
authors.initials: M
authors.lastname: Micoulaut
authors.forename: W
authors.initials: W
authors.lastname: Huff