| DOI | Trouver le DOI : https://doi.org/10.1063/1.475936 |
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| Auteur | Rechercher : Bérces, A.; Rechercher : Hackett, P. A.; Rechercher : Lian, Li; Rechercher : Mitchell, S. A.; Rechercher : Rayner, D. M. |
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| Format | Texte, Article |
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| Sujet | cluster reactivity; niobium; density functional theory; charge transfer; cluster formation reactions |
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| Résumé | Absolute rate coefficients are reported for reactions of Nbₙ clusters(n=2–20) with D₂ and N₂ at 280, 300, and 370 K. Most clusters are highly reactive but there are conspicuous exceptions at n=8, 10, and 16 for both D₂ and N₂. The origin of this trend in reactivity with cluster size and the reason why D₂ and N₂ show similar trends are discussed. Density functional theory(DFT)electronic structure calculations have been used to investigate the details of the reactions for the smallest clusters Nb₂ and Nb₈ with H₂ and N₂. The steric and electronic requirements for dissociation of H₂ and N₂ are described in terms of frontier orbital interactions. The main conclusion from the DFT calculations is that complete dissociation of H₂ or N₂ requires charge transfer by transit of an avoided crossing between neutral and ionic potentials. This idea is extended to larger clusters by using a simple charge transfer model that predicts an inverse correlation between reactivity and an appropriately defined effective ionization potential. Such a correlation is observed and indicates that the effective ionization potential is the dominant influence on reactivity. |
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| Date de publication | 1998-04-01 |
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| Dans | |
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| Langue | anglais |
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| Publications évaluées par des pairs | Oui |
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| Numéro NPARC | 21277562 |
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| Exporter la notice | Exporter en format RIS |
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| Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
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| Identificateur de l’enregistrement | cdcdba68-9361-4a32-9b9c-47684347c0dd |
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| Enregistrement créé | 2016-04-19 |
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| Enregistrement modifié | 2020-03-20 |
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