Department of Materials Science and Engineering, Lviv Polytechnic National University, Ukraine, Lviv, Ustiyanovycha 5
Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Ukraine, Lviv, Kyryla & Mephodiya street 6

Abstract

The studied TmNiSb alloy crystallizes in the MgAgAs structure type (half-Heusler phases) and according to the results of DFT+U calculations revealed the presence of bandgap (Eg = 359 meV). Spin magnetic moment of Tm atoms equals 2.16 μB confirming its Tm3+ state. Calculated elastic properties as well as Vickers hardness of TmNiSb alloy was defined semi-empirically and equals 15.98 GPa. Experimentally determined microhardness is within the range of 2.90 – 4.06 GPa with the exception of TmNiSb phase.

Keywords

thermoelectric material

DFT+U modeling

halfHeusler phases

spin magnetic moment

mechanical properties

References

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Experimental and First-principle study of TmNiSb half-Heusler Alloy