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In this research, the (001) nano-surfaces of SbNSr 3 with SbSr and NSr 2 terminations are investigated using the hybrid density functional theory (DFT) calculations. The structural, energetic, and electronic properties and also surface passivation effects are studied for different thicknesses of the nano-surfaces. The calculations showed that the surface rumpling of the SbSr termination was larger than that of the NSr 2 termination. The surface energy evaluation indicated that the difference in surface energy for the two terminations of (001) SbNSr 3 nano-surfaces was about 0.002 eV/Å2. Therefore, it can be said that both SbSr- and NSr 2 -terminated (001) surfaces of SbNSr 3 are stable. Both types of nano-surfaces demonstrated a metallic nature due to the surface states while the bulk has a semiconducting character. Hydrogen atoms were used for surface passivation to remove the surface states in the band gap. The hydrogen passivation opened the band gap for both types of nano-surfaces. The calculated band gap of the SbSr termination was smaller than that of the NSr 2 termination. The opened band gap in the SbSr-terminated nano-surfaces with the thicknesses of 3L–9L varied between 0.672 eV, 0.415 eV, 0.840 eV, and 0.808 eV. The calculated band gaps of the NSr 2 -terminated nano-surfaces were 1.776, 1.033, 1.249, and 1.029 eV for the thicknesses of 3L, 5L, 7L and, 9L, respectively. • The (001) nano-surfaces of SbNSr 3 are theoretically investigated. • The SbSr termination has stronger rumpling parameter than the NSr 2 termination. • The electronic surface state are removed by hydrogen passivation. • The opened band gap of the NSr 2 termination larger than that of the SbSr termination. [ABSTRACT FROM AUTHOR]

• The calculations of the structural, electronic, and magnetic properties of new full Heusler alloys Co 2 ZrZ (Z = Pb, Bi, As) were performed. • The most stable structure of these compounds is Cu 2 MnAl with the L2 1 structure. • The majority and minority of DOS show that the Co 2 ZrPb compound has half-metallic nature with a band gap of 0.33 eV. • The band structure and DOS of Co 2 ZrBi and Co 2 ZrAs compounds exhibit ferromagnetic metallic nature of alloys. In this paper, the calculations of the structural, electronic, and magnetic properties of new full Heusler Co 2 ZrZ (Z = Pb, Bi, As) alloys were investigated within the framework of the density functional theory (DFT). Calculations were performed using the Quantum-Espresso package and ultrasoft pseudopotential, based on generalized-gradient approximation (GGA) as the exchange–correlation potential. Using ab initio calculations, properties such as equilibrium lattice constants (a 0), bulk modulus (B), electronic band structures, majority and minority of density of states (DOS), as well as the total and atomic magnetic moments of these new compounds were calculated. The results show that the most stable structure of these compounds is the Cu 2 MnAl phase with a L2 1 crystal structure. The calculation of the electronic band structure and the majority and minority of DOS show that the Co 2 ZrPb compound has half-metallic nature with a band gap of 0.33eV. However, based on the band structure and total and partial DOS, the Co 2 ZrBi and Co 2 ZrAs compounds exhibit ferromagnetic metallic nature. In addition, the calculation of the magnetic properties indicates that the Co 2 ZrPb has a total magnetic moment of 2µ B , which follows the Slater-Pauling (SP) rule. [ABSTRACT FROM AUTHOR]