Issue |
EPL
Volume 91, Number 6, September 2010
|
|
---|---|---|
Article Number | 66007 | |
Number of page(s) | 6 | |
Section | Condensed Matter: Structural, Mechanical and Thermal Properties | |
DOI | https://doi.org/10.1209/0295-5075/91/66007 | |
Published online | 11 October 2010 |
Localized diffusive motion on two different time scales in solid alkane nanoparticles
1
Department of Physics and Astronomy and University of Missouri Research Reactor, University of Missouri Columbia, MO 65211, USA
2
Spallation Neutron Source, Oak Ridge National Laboratory - Oak Ridge, TN 37831, USA
3
Center for Neutron Research, National Institute of Standards and Technology - Gaithersburg, MD 20899-6102, USA
4
Department of Materials Science and Engineering, University of Maryland - College Park, MD 20742, USA
5
Facultad de Física, Pontificia Universidad Católica de Chile - Santiago, Chile
Received:
26
July
2010
Accepted:
3
September
2010
High-energy-resolution quasielastic neutron scattering on three complementary spectrometers has been used to investigate molecular diffusive motion in solid nano- to bulk-sized particles of the alkane n-C32H66. The crystalline-to-plastic and plastic-to-fluid phase transition temperatures are observed to decrease as the particle size decreases. In all samples, localized molecular diffusive motion in the plastic phase occurs on two different time scales: a “fast” motion corresponding to uniaxial rotation about the long molecular axis; and a “slow” motion attributed to conformational changes of the molecule. Contrary to the conventional interpretation in bulk alkanes, the fast uniaxial rotation begins in the low-temperature crystalline phase.
PACS: 66.30.hp – Molecular crystals / 78.70.Nx – Neutron inelastic scattering / 33.15.Mt – Rotation, vibration, and vibration-rotation constants
© EPLA, 2010
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.