Theoretical study on the electronic properties and stabilities of low-index surfaces of WC polymorphs
Theoretical study on the electronic properties and stabilities of low-index surfaces of WC polymorphs
复制标题
WC多晶型物低折射率表面电子性能及稳定性的理论研究
DOI：
10.1016/j.commatsci.2010.10.033
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发表时间：
2011-01-01
影响因子：
3.3
通讯作者：
Yi, Dawei
中科院分区：
文献类型：
--
作者：
Li, Yefei;Gao, Yimin;Yi, Dawei
The low-index surfaces of WC polymorphs are calculated using the first-principles method based on density functional theory. It is found that there are large relaxations within the top three layers for all termination surfaces, and charge density falls greatly toward the vacuum. The outermost and second interlayer relaxations for C-terminated surfaces are much larger than those for W-terminated surfaces. The surface energies for all low-index surfaces are large which is due to the breaking of strong W-C bonds. For both WC polymorphs, the C-termination surfaces are thermodynamically more unstable than W-terminated surfaces over the whole range of carbon chemical potentials considered in this paper; the most stable surfaces correspond to the (0 0 1) surface with W termination for alpha-WC, and the (0 0 1) surface with WC termination for beta-WC. (C) 2010 Elsevier B.V. All rights reserved.
