| Autor: |
Olson, E. A., Efremov, M. Yu., Zhang, M., Zhang, Z., Allen, L. H. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 2/1/2005, Vol. 97 Issue 3, p034304, 9p, 1 Black and White Photograph, 1 Diagram, 3 Charts, 9 Graphs |
| Abstrakt: |
Nanocalorimetry was used to investigate the melting of Bi nanoparticles. The particles were formed by evaporating Bi onto a silicon nitride substrate, which was then heated. The particles self-assemble into truncated spherical particles. Below 5-nm average film thickness, mean particle sizes increased linearly with deposition thickness but increased rapidly for 10-nm-thick films. As expected, small particles were found to exhibit size-dependent melting temperatures less than the bulk melting temperature (e.g., ΔT=67 K for a 3-nm radius particle). The measured melting temperatures for particles below ∼7 nm in radius, however, were ∼50 K above the value predicted by the homogeneous melting model. We discuss this discrepancy in terms of a possible size-dependent crystal structure change and the superheating of the solid phase. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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