A theoretical study of the reactivity of Pd clusters with methane
- Univ. of Stockholm (Sweden)
Correlated, size-consistent calculations have been performed for the reaction between Pd{sub 2} and CH{sub 4}. Some calculations have also been done for Pd{sub 3}. The results are used to interpret the experimental observations for the reactivity of palladium clusters of different sizes with CH{sub 4}. The calculations indicate that the C-H bond is broken with only a small barrier of 4-6 kcal/mol and thus confirm the experimental interpretation of dissociative chemisorption. This result is in contrast to the case of N{sub 2}, which was found in calculations to be only molecularly bound. There are two dominating effects for the size of the barrier in the methane reaction. The first factor is the repulsion in the entrance channel, and the other factor is the capability of strong bond formation in the product channel. For palladium clusters of different sizes these two effects compete, and this is the origin for the maximum in the curve for the reactivity versus cluster size found experimentally at about 10 atoms. 29 refs., 2 figs., 3 tabs.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 273594
- Journal Information:
- Journal of Physical Chemistry, Journal Name: Journal of Physical Chemistry Journal Issue: 14 Vol. 96; ISSN JPCHAX; ISSN 0022-3654
- Country of Publication:
- United States
- Language:
- English
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