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Title: Preferred orientations and stability of medium length n-alkanes solidified in mesoporous silicon

Abstract

The n-alkanes C{sub 16}H{sub 34}, C{sub 17}H{sub 36}, C{sub 19}H{sub 40}, and C{sub 25}H{sub 52} have been imbibed and solidified in mesoporous, crystalline silicon with a mean pore diameter of 10 nm. The structures and phase sequences have been determined by x-ray diffractometry. Apart from a reduction and the hysteresis of the melting-freezing transition, we find a set of six discrete orientation states (''domains'') of the confined alkane crystals with respect to the lattice of the silicon host. The growth process responsible for the domain selection is interpreted as a nanoscale version of the Bridgman technique known from single-crystal growth. Oxidation of the pore walls leads to extrusion of the hydrocarbons upon crystallization, whereas the solidified n-alkanes investigated in nonoxidized, porous silicon are thermodynamically stable.

Authors:
; ; ;  [1]
  1. Technische Physik, Universitaet des Saarlandes, D-66041 Saarbruecken (Germany)
Publication Date:
OSTI Identifier:
21072377
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevE.75.021607; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALKANES; CRYSTAL GROWTH; CRYSTALLIZATION; FREEZING; GRAIN ORIENTATION; HYSTERESIS; MELTING; MONOCRYSTALS; NANOSTRUCTURES; OXIDATION; PHASE STABILITY; POROSITY; POROUS MATERIALS; SILICON; SOLIDIFICATION; TEXTURE; X-RAY DIFFRACTION

Citation Formats

Henschel, A., Hofmann, T., Huber, P., and Knorr, K. Preferred orientations and stability of medium length n-alkanes solidified in mesoporous silicon. United States: N. p., 2007. Web. doi:10.1103/PHYSREVE.75.021607.
Henschel, A., Hofmann, T., Huber, P., & Knorr, K. Preferred orientations and stability of medium length n-alkanes solidified in mesoporous silicon. United States. doi:10.1103/PHYSREVE.75.021607.
Henschel, A., Hofmann, T., Huber, P., and Knorr, K. Thu . "Preferred orientations and stability of medium length n-alkanes solidified in mesoporous silicon". United States. doi:10.1103/PHYSREVE.75.021607.
@article{osti_21072377,
title = {Preferred orientations and stability of medium length n-alkanes solidified in mesoporous silicon},
author = {Henschel, A. and Hofmann, T. and Huber, P. and Knorr, K.},
abstractNote = {The n-alkanes C{sub 16}H{sub 34}, C{sub 17}H{sub 36}, C{sub 19}H{sub 40}, and C{sub 25}H{sub 52} have been imbibed and solidified in mesoporous, crystalline silicon with a mean pore diameter of 10 nm. The structures and phase sequences have been determined by x-ray diffractometry. Apart from a reduction and the hysteresis of the melting-freezing transition, we find a set of six discrete orientation states (''domains'') of the confined alkane crystals with respect to the lattice of the silicon host. The growth process responsible for the domain selection is interpreted as a nanoscale version of the Bridgman technique known from single-crystal growth. Oxidation of the pore walls leads to extrusion of the hydrocarbons upon crystallization, whereas the solidified n-alkanes investigated in nonoxidized, porous silicon are thermodynamically stable.},
doi = {10.1103/PHYSREVE.75.021607},
journal = {Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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