| Raman scattering studies on n-heptane under high pressure. | |
| | |
MedLine Citation:
|
PMID: 16640435 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
High-pressure Raman scattering studies at ambient temperature are performed on n-heptane. We observe a liquid-solid transition around 1.5 GPa from the changes in the Raman spectra. This has been reported in earlier works. With increasing pressure, we observe large changes in the Raman modes and the spectra show a distinct change around 7.5 GPa. This marks the solid-solid transition at 7.5 GPa observed in n-heptane for the first time. As predicted in theoretical work, we observe dampening of methyl rotation in n-heptane below 7.5 GPa. With increase in pressure above 7.5 GPa we observe a definitive conversion of gauche to trans conformation in the solid phase. Upon release of pressure we do not observe any hysteresis, which suggests that the solid-solid transition takes place with no volume change or is a second-order transition. In this paper we propose this transition to be an orientational order-disorder transition driven by the dampening of the rotation of the methyl group. |
| | |
Authors:
|
G Kavitha; Chandrabhas Narayana |
Related Documents
:
|
16687835 - High-pressure solution x-ray scattering of protein using a hydrostatic cell with diamon... 19287735 - Reproduction of globodera rostochiensis on transformed roots of solanum tuberosum cv. d... 18266365 - Pressure-induced hydration and order-disorder transition in a synthetic potassium gallo... 12082275 - The effects of pressure on chondrocyte tumour necrosis factor receptor expression. 7326875 - Differing noradrenaline kinetics in essential hypertension and depressive illness, two ... 6863085 - Effect of diaphragm contraction on canine heart and pericardium. |
Publication Detail:
|
Type: Journal Article |
Journal Detail:
|
Title: The journal of physical chemistry. B Volume: 110 ISSN: 1520-6106 ISO Abbreviation: J Phys Chem B Publication Date: 2006 May |
Date Detail:
|
Created Date: 2006-04-27 Completed Date: 2007-07-30 Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 101157530 Medline TA: J Phys Chem B Country: United States |
Other Details:
|
Languages: eng Pagination: 8777-81 Citation Subset: IM |
Affiliation:
|
Chemistry and Physics of Material Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore 560 064, India. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Heptanes
/
chemistry* Lasers Light Pressure Reference Standards Scattering, Radiation Sensitivity and Specificity Spectrum Analysis, Raman / methods*, standards Vibration |
| Chemical | |
Reg. No./Substance:
|
0/Heptanes; 142-82-5/n-heptane |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Identification of destabilized metal hydrides for hydrogen storage using first principles calculatio...
Next Document: Monte Carlo simulations of the hydrophobic effect in aqueous electrolyte solutions.