title: Picosecond dynamics and microheterogenity of water+dioxane mixtures.
abstract: Dielectric spectra from 200 MHz up to 3 THz were determined to study the fast dynamics of dilute water+1,4-dioxane. epsilon(nu) could be fitted by a collision induced oscillator at high frequencies plus two Debye relaxations in the microwave region. Isotope substitution was used to assign water and dioxane modes. The presence of the cooperative hydrogen-bond network relaxation down to a water mole fraction of 0.005 suggests a microheterogeneous structure of the mixtures even at low water content. The collision mode of dioxane at approximately 2 THz grows upon water addition, revealing the presence of H2O molecules in dioxane-rich domains.
authors: Institute of Physical and Theoretical Chemistry, Universität Regensburg, D-93040 Regensburg, Germany.
authors: Simon
authors: S
authors: Schrödle
authors: Bernd
authors: B
authors: Fischer
authors: Hanspeter
authors: H
authors: Helm
authors: Richard
authors: R
authors: Buchner
mesh_terms: D004146:Dioxanes / Q000737:chemistry*; D004583:Electrons; D007201:Indicator Dilution Techniques; D012996:Solutions; D013057:Spectrum Analysis; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry*
chemical_list: D004146:Dioxanes; D012996:Solutions; D014867:Water; C025223:1,4-dioxane