Half-metallic fully compensated ferrimagnetism in C1_b-type half Heusler compounds Mn₂Si_1−xGe_x

First-principles electronic structure calculations have been performed for the 18-valence electrons compounds Mn₂Si_1−xGe_x(x=0, 0.25, 0.5, 0.75, 1). The results suggest that Mn₂Si_1−xGe_x compounds in C1_b structure are half-metallic fully compensated ferrimagnets. Furthermore, the size of the half-metallic band gap, the position of the Fermi level, and the magnetic moment of Mn atoms can be manipulated by changing x from 0 to 1 without destroying the half-metallic fully compensated ferrimagnetic property. - Highlights: • Confirmed the most favorable crystal structure for Mn₂Si_1−xGe_x is C1_b structure. • Predicted that Mn₂Si_1−xGe_x were half-metallic fully compensated ferrimagnets. • Proposed a way to modulate the gap and the position of the Fermi level