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Title: Driving Force for the WO3(001) Surface Relaxation

Abstract

The optimized structure of the WO3(001) surface with various types of termination ((1x1)O, (1x1) WO2, and c(2x2)O) has been simulated using density functional theory with the Perdew-Wang 91 gradient-corrected exchange correlation functional. While energy of bulk WO3 depends weakly on the distortions and tilting of the WO6 octahedra, relaxation the (001) surface results in a significant decrease of surface energy (from 10.2x10-2 eV/Å2 for bulk-extracted, ReO3-like, c(2x2)O-terminated surface to 2.2x10-2 eV/Å2 for the relaxed surface). This feature illustrates important role of surface in formation of crystalline nano-size clusters of WO3. The surface relaxation is accompanied by a dramatic redistribution of density of states near the Fermi level, in particular the transformations of surface electronic states. This redistribution is responsible for the decrease of electronic energy and therefore is suggested to be the driving force for surface relaxation of the WO3(001) surface and, presumably, similar surfaces of other transition metal oxides. Battelle operates PNNL for the USDOE.

Authors:
;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
902683
Report Number(s):
PNNL-SA-48459
Journal ID: ISSN 0039-6028; SUSCAS; 3568; KC0302010; TRN: US200718%%57
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Surface Science, 601(6):1481-1488; Journal Volume: 601; Journal Issue: 6
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; TUNGSTEN OXIDES; FERMI LEVEL; DENSITY FUNCTIONAL METHOD; STRESS RELAXATION; SURFACE ENERGY; transition metal oxide surfaces; WO3(001) surface; surface relaxation; density of states; surface electronic structure; density funtional theory; Environmental Molecular Sciences Laboratory

Citation Formats

Yakovkin, Ivan N., and Gutowski, Maciej S. Driving Force for the WO3(001) Surface Relaxation. United States: N. p., 2007. Web. doi:10.1016/j.susc.2007.01.013.
Yakovkin, Ivan N., & Gutowski, Maciej S. Driving Force for the WO3(001) Surface Relaxation. United States. doi:10.1016/j.susc.2007.01.013.
Yakovkin, Ivan N., and Gutowski, Maciej S. Thu . "Driving Force for the WO3(001) Surface Relaxation". United States. doi:10.1016/j.susc.2007.01.013.
@article{osti_902683,
title = {Driving Force for the WO3(001) Surface Relaxation},
author = {Yakovkin, Ivan N. and Gutowski, Maciej S.},
abstractNote = {The optimized structure of the WO3(001) surface with various types of termination ((1x1)O, (1x1) WO2, and c(2x2)O) has been simulated using density functional theory with the Perdew-Wang 91 gradient-corrected exchange correlation functional. While energy of bulk WO3 depends weakly on the distortions and tilting of the WO6 octahedra, relaxation the (001) surface results in a significant decrease of surface energy (from 10.2x10-2 eV/Å2 for bulk-extracted, ReO3-like, c(2x2)O-terminated surface to 2.2x10-2 eV/Å2 for the relaxed surface). This feature illustrates important role of surface in formation of crystalline nano-size clusters of WO3. The surface relaxation is accompanied by a dramatic redistribution of density of states near the Fermi level, in particular the transformations of surface electronic states. This redistribution is responsible for the decrease of electronic energy and therefore is suggested to be the driving force for surface relaxation of the WO3(001) surface and, presumably, similar surfaces of other transition metal oxides. Battelle operates PNNL for the USDOE.},
doi = {10.1016/j.susc.2007.01.013},
journal = {Surface Science, 601(6):1481-1488},
number = 6,
volume = 601,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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