Preparation and physical properties of antiperovskite-type compounds CdNCo_(3-z)Ni_z (0≤z≤3)

摘要

A series of CdNCo_(3-z)Ni_z (0≤z≤3) samples were prepared from CdO and metal powders under NH_3 atmosphere at 743 K. The structural and physical properties were investigated by means of X-ray powder diffraction, temperature dependent resistivity and magnetic measurements. X-ray powder diffraction results show that CdNCo_3 is a new ternary nitride with antiperovskite structure, and it can form a complete solid solution series with CdNNi_3. Both CdNCo_3 and CdNNi_3 samples show metallic temperature dependent resistivity and exhibit a Fermi liquid behavior below 50 K. All samples are ferromagnetic, and their coercivity and remanence decrease as the Ni content increases. The temperature dependence of the magnetization of the CdNCo_(3-z)Ni_z samples can be well fitted to the combination of a Bloch term and a Curie-Weiss term. The CdNCo_3 sample is ferromagnet with coercivity of 240 Oe at room-temperature. In contrast to the paramagnetism previously reported, our CdNNi_3 sample exhibits very soft and weak ferromagnetism.