Ni-doping effect on the magnetic transition and correlated lattice contraction in antiperovskite Mn3ZnN compounds

The Ni-doping effect on the lattice and magnetic properties in Mn3Zn1−xNixN was first reported. The ground-state magnetic structure for Mn3ZnN is noncollinear antiferromagnetic Γ5gΓ5g. The introduction of Ni-doping induces a continuous spin rotation in the (111) plane from Γ5gΓ5g to weak ferromagnetic Γ4gΓ4g configurations, exhibiting a change from antiferromagnetic to weak ferromagnetic with increasing Ni content. In particular, when Ni content increased to x≥0.5x≥0.5, Mn3Zn1−xNixN shows an abrupt lattice contraction near the magnetic transition with increasing temperature. The normal–abnormal lattice variation in Mn3Zn1−xNixN is explained by the competition between the negative free energy variation δFeδFe and the positive δF0δF0.

► We investigated Ni-doping effect on the lattice and magnetic properties of Mn3ZnN. ► We note that the AFM phase is replaced by the weak ferromagnetic phase with increasing Ni content. ► The evolution of magnetic structure with Ni-doping content is attributed to spin rotation. ► The lattice contraction originates from the large negative electronic contribution δFeδFe.