First-principles investigation of the vacancy effect on the electronic properties in M{sub 2}AlC(M = V and Nb)
- College of Mathematics and Statistics, Long Dong University, QingYang 745000 (China)
- Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000 (China)
First principles calculations have been performed to study the mono-vacancy formation energies and electronic properties of M{sub 2}AlC (M = V and Nb) compound. The results show that the M mono-vacancy has a maximum formation energy. While the C mono-vacancy has a minimum formation energy, which means that the C mono-vacancy is the energetically most favorable in M{sub 2}AlC. The d-electrons of M element contribute most to the DOS of M{sub 2}AlC around the Fermi level, it implies that the conductivity of M{sub 2}AlC comes from the transition metal M. The M-C bond is stronger than the M-Al bond, which is caused by the strong hybridization energy peak between M and C atom. In addition, the M-C bond is weaken in the presence of the M or C mono-vacancy. The cell volumes are reduced when the mono-vacancy is formed. These results help us to understand the origin of the defect-related properties and phase stability of V{sub 2}AlC and Nb{sub 2}AlC under extreme environment.
- OSTI ID:
- 22299629
- Journal Information:
- AIP Advances, Vol. 4, Issue 10; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 2158-3226
- Country of Publication:
- United States
- Language:
- English
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