| Autor: |
León-Gutierrez E; Group of Nanomaterials and Microsystems, Department of Physics, Universitat Autonoma de Barcelona, Campus UAB, 08193 Bellaterra, Spain., Garcia G, Lopeandía AF, Fraxedas J, Clavaguera-Mora MT, Rodríguez-Viejo J |
| Jazyk: |
angličtina |
| Zdroj: |
The Journal of chemical physics [J Chem Phys] 2008 Nov 14; Vol. 129 (18), pp. 181101. |
| DOI: |
10.1063/1.3009766 |
| Abstrakt: |
In this work, we describe the design and first experimental results of a new setup that combines evaporation of liquids in ultrahigh vacuum conditions with in situ high sensitivity thermal characterization of thin films. Organic compounds are deposited from the vapor directly onto a liquid nitrogen cooled substrate, permitting the preparation and characterization of glassy films. The substrate consists of a microfabricated, membrane-based nanocalorimeter that permits in situ measurements of heat capacity under ultrafast heating rates (up to 10(5) K/s) in the temperature range of 100-300 K. Three glass forming liquids-toluene, methanol, and acetic acid-are characterized. The spikes in heat capacity related to the glass-transition temperature, the fictive temperature and, in some cases, the onset temperature of crystallization are determined for several heating rates. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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