Synthesis and characterization of antiperovskite nitrides GaNCr3−xMnx

The effects of Mn-doping on the crystal structure, magnetic and electrical/thermal transport properties of GaNCr3−xMnx (0≤x≤1.5) have been investigated systematically. As a result, the lattice constant and the residual resistivity increase, while the residual resistivity ratio, electron thermal conductivity, and room-temperature carrier concentration decrease with increasing Mn-doping level. The ground state of parent compound GaNCr3 is nonmagnetic, interestingly, the ferrimagnetism and antiferromagnetism are observed in Mn-doped samples GaNCr3−xMnx. Correspondingly, around the antiferromagnetic transition of GaNCr3−xMnx the correlation effect is studied. Furthermore, the analysis of thermal conductivity data suggests that the electron thermal conductivity plays a major role in total thermal conductivity of GaNCr3 at low temperatures, while the phonon thermal conductivity is dominant for Mn-doped GaNCr3 in the whole temperature of 5–330K. The positive values of Seebeck coefficient and Hall coefficient indicate that the nature of charge carrier is hole-type in GaNCr3−xMnx. The Rietveld refinement and structural properties of GaNCr3−xMnx. [Display omitted] •Polycrystalline GaNCr3−xMnx are synthesized by using the solid state reaction method.•A good quality of samples is verified by Rietveld refinement and RRR values.•Antiferromagnetic and ferromagnetic competitions are induced by Mn-doping.•We present a comprehensive understanding of physical properties of GaNCr3−xMnx.