Electronic structure and structural stability of (Ba0.75Ae0.25)Fe2As2 (Ae = Li, Na, Rb)

• Electronic structure and structural stability of (Ba 0.75 Ae 0.25 )Fe 2 As 2 (Ae = Li, Na and Rb) were studied. • The Ae atoms doping caused the movement of the Fermi level, which led to the reconstruction of Fermi surface. • Ae atoms were not easily soluble in BaFe 2 As 2 . • With the increase of Ae ion radius, the stability of doped system decreased and doping became more difficult. Electronic structure and structural stability of (Ba 0.75 Ae 0.25 )Fe 2 As 2 (Ae = Li, Na and Rb) have been studied by first principles calculations. After the introduction of Ae atoms, the magnetic moment was reduced. The Ae atoms doping increased the number of carriers in BaFe 2 As 2 and caused the movement of the Fermi level, which led to the reconstruction of Fermi surface. The calculated results of formation energy, Gibbs free energy and phonon dispersion showed that Ae atoms were not easily soluble in BaFe 2 As 2 . BaFe 2 As 2 doped system was unstable after Ae atoms were introduced. With the increase of ion radius of introduced Ae atoms, the stability of doped system decreased and doping became more difficult.