Ti2FeZ (Z=Al, Ga, Ge) alloys: Structural, electronic, and magnetic properties

• Ti2FeZ (Z=Al, Ga, Ge) are found to be half-metallic ferrimagnets.
• The band gaps are mainly determined by the hybridizations of the d states between the Ti(A)–Ti(B) coupling and Fe atom.
• The s–p elements play an important role in the half-metallicity of these Heusler alloys.

Using the first-principle projector augmented wave potential within the generalized gradient approximation taking into account the on-site Coulomb repulsive, we investigate the structural, electronic and magnetic properties of Ti2FeZ (Z=Al, Ga, Ge) alloys with Hg2CuTi-type structure. These alloys are found to be half-metallic ferrimagnets. The total magnetic moments of the Heusler alloys Ti2FeZ follow the µt=Zt−18 rule and agree with the Slater–Pauling curve quite well. The band gaps are mainly determined by the bonding and antibonding states created from the hybridizations of the d states between the Ti(A)–Ti(B) coupling and Fe atom.