Simulation of structural and electronic properties of amorphous tungsten oxycarbides

Kaliappan Muthukumar, Roser Valentí, Harald Olaf Jeschke

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Electron beam-induced deposition with tungsten hexacarbonyl W(CO) 6 as precursors leads to granular deposits with varying compositions of tungsten, carbon and oxygen. Depending on the deposition conditions, the deposits are insulating or metallic. We employ an evolutionary algorithm to predict the crystal structures starting from a series of chemical compositions that were determined experimentally. We show that this method leads to better structures than structural relaxation based on estimated initial structures. We approximate the expected amorphous structures by reasonably large unit cells that can accommodate local structural environments that resemble the true amorphous structure. Our predicted structures show an insulator-to-metal transition close to the experimental composition at which this transition is actually observed and they also allow comparison with experimental electron diffraction patterns.

Original languageEnglish
Article number113028
JournalNew Journal of Physics
Volume14
DOIs
Publication statusPublished - Nov 2012
Externally publishedYes

Fingerprint

tungsten
deposits
electronics
chemical composition
diffraction patterns
electron diffraction
simulation
transition metals
insulators
electron beams
crystal structure
carbon
oxygen
cells

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Simulation of structural and electronic properties of amorphous tungsten oxycarbides. / Muthukumar, Kaliappan; Valentí, Roser; Jeschke, Harald Olaf.

In: New Journal of Physics, Vol. 14, 113028, 11.2012.

Research output: Contribution to journalArticle

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