首页 | 本学科首页   官方微博 | 高级检索  
     


Accommodation of impurities in α-Al2O3, α-Cr2O3 and α-Fe2O3
Authors:K. J. W. Atkinson   Robin W. Grimes   Mark R. Levy   Zoe L. Coull  Tim English
Affiliation:a Department of Materials, Imperial College, London SW7 2BP, UK;b The Royal Institution, 21 Albermarle St., London W1X 4BS, UK;c Los Alamos National Laboratory, Los Alamos, NM 87545, USA;d Corus UK Ltd, Swinden Technology Centre, Moorgate Road, Rotherham S60 3AR, UK
Abstract:
Atomic scale computer simulation was used to predict the mechanisms and energies associated with the accommodation of aliovalent and isovalent dopants in three host oxides with the corundum structure. Here we consider a much more extensive range of dopant ions than has previously been the case. This enables a rigorous comparison of calculated mechanism energetics. From this we predict that divalent ions are charge compensated by oxygen vacancies and tetravalent ions by cation vacancies over the full range of dopant radii. When defect associations are included in the model these conclusions remain valid. At equilibrium, defects resulting from extrinsic dopant solution dominate intrinsic processes, except for the largest dopant cations. Solution reaction energies increase markedly with increasing dopant radius. The behaviour of cluster binding energies is more complex.
Keywords:Al2O3   Cr2O3   Detect chemistry   Dopants   Fe2O3   Impurities   Simulations
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号