Autor: |
Colleen M. Neal, Martin F. Jarrold, Anne K. Starace |
Rok vydání: |
2007 |
Předmět: |
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Zdroj: |
Journal of the American Society for Mass Spectrometry. 18:74-81 |
ISSN: |
1044-0305 |
DOI: |
10.1016/j.jasms.2006.08.019 |
Popis: |
Calorimetry measurements have been used to probe the melting of aluminum cluster cations with 63 to 83 atoms. Heat capacities were determined as a function of temperature (from 150 to 1050 K) for size-selected cluster ions using an approach based on multicollision-induced dissociation. The experimental method is described in detail and the assumptions are critically evaluated. Most of the aluminum clusters in the size range examined here show a distinct peak in their heat capacities that is attributed to a melting transition (the peak is due to the latent heat). The melting temperatures are below the bulk melting point and show enormous fluctuations as a function of cluster size. Some clusters (for example, n = 64, 68, and 69) do not show peaks in their heat capacities. This behavior is probably due to the clusters having a disordered solid-like phase, so that melting occurs without a latent heat. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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