Article
High Pressure Studies on the Planarity of Para-hexaphenyl
Synthetic Metals
Abstract
We present experimental and theoretical findings on the geometry of para-hexaphenyl (PHP) molecules in polycrystalline powder. A new method to assess the planarity of PHP via Raman spectroscopy is presented. Based on this method we describe a W-shaped potential energy curve which governs the torsional motion between neighboring phenyl rings. We determine the activation energy to promote PHP from a non-planar to a planar state to be 0.04 eV, in good agreement with our quantum chemical calculations. Finally we are able to experimentally planarize the molecules by the application of hydrostatic pressure, which modifies the W-shaped potential energy curve to a U-shaped one.
Department(s)
Chemistry
Sponsor(s)
Conseil Regional du Languedoc-RoussillonDistrict de Montpellier
Ministere de l'Education Nationale
Universite de Montpellier II
Keywords and Phrases
- Activation energy,
- Electron energy levels,
- High pressure effects,
- Molecular structure,
- Probability density function,
- Quantum theory,
- Raman spectroscopy,
- Activation energy,
- Hydrostatic pressure,
- Molecular dynamics,
- Polycrystalline materials,
- Potential energy,
- Quantum theory,
- Raman spectroscopy,
- Density functional calculations,
- Para hexaphenyl,
- Phenyl rings,
- Quantum chemical calculations,
- Semiconducting organic compounds,
- Semiconducting organic compounds,
- Density functional theory,
- Parahexaphenyl
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 1999 Elsevier Sequoia SA, Lausanne, All rights reserved.
Publication Date
5-1-1999
Publication Date
01 May 1999
Disciplines
Citation Information
Suchismita Guha, Wilhelm Graupner, Roland Resel, Meera Chandrasekhar, et al.. "High Pressure Studies on the Planarity of Para-hexaphenyl" Synthetic Metals Vol. 101 Iss. 1-3 (1999) p. 180 - 181 ISSN: 0379-6779 Available at: http://works.bepress.com/rainer-glaser/71/