First-principles study on electronic structure, magnetism and half-metallicity of the NbCoCrAl and NbRhCrAl compounds

First-principles study on electronic structure, magnetism and half-metallicity of the NbCoCrAl and NbRhCrAl compounds

•Half-metallicity of the NbCoCrAl and NbRhCrAl compounds are successfully proved by first-principles calculation.•The ranges of half-metallicity are 5.87–6.07Å and 5.954–6.279Å for NbCoCrAl and NbRhCrAl compounds, respectively.•The half-metallicity NbRhCrAl are more stable than that of NbCoCrAl.•The...

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Bibliographic Details
Published in:Results in physics 2017, Vol.7, p.2248-2254
Main Authors: Li, Y., Liu, G.D., Wang, X.T., Liu, E.K., Xi, X.K., Wang, W.H., Wu, G.H., Wang, L.Y., Dai, X.F.
Format: Article
Language:eng
Subjects:
First-principles calculations
Half-metallicity
Heusler compounds
Lattice thermal expansion
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Summary:•Half-metallicity of the NbCoCrAl and NbRhCrAl compounds are successfully proved by first-principles calculation.•The ranges of half-metallicity are 5.87–6.07Å and 5.954–6.279Å for NbCoCrAl and NbRhCrAl compounds, respectively.•The half-metallicity NbRhCrAl are more stable than that of NbCoCrAl.•The half-metallicity of NbRhCrAl is more robust against the lattice thermal expansion with increasing temperature. The electronic structure, magnetism and half-metallicity of quaternary Heusler compounds NbCoCrAl and NbRhCrAl were investigated theoretically by using first-principles calculations. It was found that the equilibrium lattice constants of NbCoCrAl and NbRhCrAl compounds are 6.02Å and 6.18Å, respectively. The total magnetic moment is 1μB and consistent with the Slater-Pauling formula: Mt=24−Zt. The half-metallicity can be kept when the lattice constant changes in the range of 5.87–6.07Å and 5.954–6.279Å for NbCoCrAl and NbRhCrAl compounds, respectively. The half-metallic band gap locates between the eu and t1u states originating from the hybridizations of the d states of Cr and Co (Rh) atoms. Compared with NbCoCrAl, as the radius of Rh with valance electron in 4d states is bigger than that of Co with valance electron in 3d states, NbRhCrAl has a more stable half-metallicity and bigger equilibrium lattice constant. In particular, the half-metallicity of NbRhCrAl is more robust against the lattice thermal expansion with increasing temperature.
ISSN:2211-3797
2211-3797