How to find an optimum cluster size through topological site properties : MoSx model clusters

Copyright © 2011 Wiley Periodicals, Inc.

Bibliographische Detailangaben
Veröffentlicht in:Journal of computational chemistry. - 1984. - 32(2011), 10 vom: 30. Juli, Seite 2186-94
1. Verfasser: Silva, Alexander M (VerfasserIn)
Weitere Verfasser: Borges, Itamar Jr
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2011
Zugriff auf das übergeordnete Werk:Journal of computational chemistry
Schlagworte:Journal Article DFT MoS2 cluster optimum size hydrodesulfurization molecular charge distribution
Beschreibung
Zusammenfassung:Copyright © 2011 Wiley Periodicals, Inc.
Computational investigations in catalysis frequently use model clusters to represent realistically the catalyst and its reaction sites. Detailed knowledge of the molecular charge, thus electronic density, of a cluster would then allow physical and chemical insights of properties and can provide a procedure to establish their optimum size for catalyst studies. For this purpose, an approach is suggested to study model clusters based on the distributed multipole analysis (DMA) of molecular charge properties. After full density functional theory (DFT) geometry optimization of each cluster, DMA computed from the converged DFT one-electron density matrix allowed the partition of the corresponding cluster charge distribution into monopole, dipole, and quadrupole moments on the atomic sites. The procedure was applied to MoS2 model clusters Mo10S18, Mo12S26, Mo16S32, Mo23S48, and Mo27S54. This analysis provided detailed features of the charge distribution of each cluster, focused on the 1010 (Mo or metallic edge) and 1010 (sulfur edge) active planes. Properties of the Mo27S54 cluster, including the formation of HDS active surfaces, were extensively discussed. The effect of cluster size on the site charge distribution properties of both planes was evaluated. The results showed that the Mo16S32 cluster can adequately model both active planes of real size Mo27S54. These results can guide future computational studies of MoS2 catalytic processes. Furthermore, this approach is of general applicability
Beschreibung:Date Completed 19.05.2015
Date Revised 03.11.2014
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1096-987X
DOI:10.1002/jcc.21802