Formation and interaction of point defects in group IVb transition metal carbides and nitrides
2015 (English)In: Computational materials science, ISSN 0927-0256, Vol. 104, 147-154 p.Article in journal, Editorial material (Other academic) Published
Point defects in the group IVb transition metal carbides and nitrides are investigated by means of density functional theory calculations. We focus on a description of a complex vacancy behavior of the sub-stoichiometric carbides and nitrides and find a strong tendency toward vacancy clustering in the carbides. Our results demonstrate that a special type of a stable point defect, a metal vacancy "dressed'' in a shell of six carbon vacancies can be a dominant type of metal-vacancy-containing defect in the carbon-deficient sub-stoichiometric carbides, whereas the simplest point defects appear to be dominant in the nitrogen-deficient sub-stoichiometric nitrides. We also show that such clusters are strongly bound in carbides and that temperature has a relatively small effect on the overall defect stability of group IVb transition metal carbides and nitrides.
Place, publisher, year, edition, pages
2015. Vol. 104, 147-154 p.
Ab initio calculations, Point defects, Carbides, Nitrides, Thermodynamic stability
IdentifiersURN: urn:nbn:se:kth:diva-168681DOI: 10.1016/j.commatsci.2015.03.042ISI: 000354184300020ScopusID: 2-s2.0-84928485602OAI: oai:DiVA.org:kth-168681DiVA: diva2:818525
QC 201506092015-06-092015-06-082015-06-09Bibliographically approved