title: Confinement for More Space: A Larger Free Volume and Enhanced Glassy Dynamics of 2-Ethyl-1-hexanol in Nanopores.
abstract: Broadband dielectric spectroscopy and positron annihilation lifetime spectroscopy are employed to study the molecular dynamics and effective free volume of 2-ethyl-1-hexanol (2E1H) in the bulk state and when confined in unidirectional nanopores with average diameters of 4, 6, and 8 nm. Enhanced α-relaxations with decreasing pore diameters closer to the calorimetric glass-transition temperature (T(g)) correlate with the increase in the effective free volume. This indicates that the glassy dynamics of 2D constrained 2E1H is mainly controlled by density variation.
authors.affiliation: Institute of Experimental Physics I, University of Leipzig , Linnéstrasse 5, 04103 Leipzig, Germany.
authors.forename: Wycliffe K
authors.initials: WK
authors.lastname: Kipnusu
authors.affiliation: Department of Physics, Martin Luther University Halle , 06099 Halle, Germany.|Department of Physics, Faculty of Science, Minia University , 61519 Minia, Egypt.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Elsayed
authors.affiliation: Institute of Experimental Physics I, University of Leipzig , Linnéstrasse 5, 04103 Leipzig, Germany.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Kossack
authors.affiliation: Institute of Physics, University of Silesia , ul. Uniwersytecka 4, 40-007 Katowice, Poland.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Pawlus
authors.affiliation: DNRF Centre "Glass and Time", IMFUFA, Department of Sciences, Roskilde University , Postbox 260, DK-4000 Roskilde, Denmark.
authors.forename: Karolina
authors.initials: K
authors.lastname: Adrjanowicz
authors.affiliation: Institute of Experimental Physics I, University of Leipzig , Linnéstrasse 5, 04103 Leipzig, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Tress
authors.affiliation: Institute of Experimental Physics I, University of Leipzig , Linnéstrasse 5, 04103 Leipzig, Germany.
authors.forename: Emmanuel U
authors.initials: EU
authors.lastname: Mapesa
authors.affiliation: Department of Physics, Martin Luther University Halle , 06099 Halle, Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Krause-Rehberg
authors.affiliation: Institute of Physics, University of Silesia , ul. Uniwersytecka 4, 40-007 Katowice, Poland.
authors.forename: Kamil
authors.initials: K
authors.lastname: Kaminski
authors.affiliation: Institute of Experimental Physics I, University of Leipzig , Linnéstrasse 5, 04103 Leipzig, Germany.
authors.forename: Friedrich
authors.initials: F
authors.lastname: Kremer
keywords: Debye process; confinement; free volume; nanopores; structural relaxation