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dc.contributor.authorMuñoz, Ramo Daviden
dc.contributor.authorBristowe, Paul Den
dc.date.accessioned2014-03-17T09:48:17Z
dc.date.available2014-03-17T09:48:17Z
dc.date.issued2014-03-31en
dc.identifier.citationThin Solid Films 555: 112-116. DOI: 10.1016/j.tsf.2013.08.013en
dc.identifier.issn0040-6090
dc.identifier.urihttps://www.repository.cam.ac.uk/handle/1810/245209
dc.description.abstractWe report density functional calculations of the atomic and electronic structure of the spinel phases ZnRh2O4 and ZnIr2O4 as well as crystalline ZnO lightly doped (1 at.%) with Rh and Ir ions using the B3LYP hybrid functional. Calculations for the spinels show band gaps (∼3 eV) and lattice parameters (∼2% difference) in reasonable agreement with experimental data. Incorporation of the transition metals into ZnO induces local distortions in the lattice and the appearance of metal d levels in the low gap region and near the conduction band minimum, with a d-d splitting larger than 2 eV, which helps maintain transparency in the material. Addition of a hole to the simulation cell of both spinels and doped ZnO leads to charge localization in the neighbourhood of Rh/Ir accompanied by local lattice deformations to form a small polaron which may lead to low hole mobility. We calculate polaron diffusion barriers in the spinels and obtain values around 0.02-0.03 eV. These very low barrier energies suggest that at high Rh/Ir concentration hole conduction occurs mainly by the band conduction mechanism at room temperature. We also develop models of the amorphous spinels by means of classical molecular dynamics simulations, and observe a marked reduction in the coordination number of Rh/Ir, from 6 to 4, in the amorphous phase, which may reduce transparency in these materials.
dc.description.sponsorshipFinancial support for this work is provided by the European Commission through contract No. NMP3-LA-2010-246334 (ORAMA).
dc.languageEnglishen
dc.language.isoenen
dc.publisherElsevier
dc.titleHybrid density functional calculations of the defect properties of ZnO:Rh and ZnO:Iren
dc.typeArticle
dc.description.versionThis is the originally submitted version of the article, and does not include any of the changes arising from peer-review. The final, peer-reviewed and edited version of the article is available at http://www.sciencedirect.com/science/article/pii/S0040609013013059.en
prism.endingPage116
prism.publicationDate2014en
prism.publicationNameThin Solid Filmsen
prism.startingPage112
prism.volume555en
rioxxterms.versionofrecord10.1016/j.tsf.2013.08.013en
rioxxterms.licenseref.urihttp://www.rioxx.net/licenses/all-rights-reserveden
rioxxterms.licenseref.startdate2014-03-31en
dc.identifier.eissn1879-2731
rioxxterms.typeJournal Article/Reviewen


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