Structural, magnetic and transport properties of Mn_(3.1)Sn_(0.9) and Mn_(3.1)Sn_(0.9)N compounds

摘要

The cubic anti-perovskite Mn_(3.1)Sn_(0.9)N compound is prepared via nitrogenation of the hexagonal Mn_(3.1)Sn_(0.9) compound. A magnetic phase diagram of Mn_(3.1)Sn_(0.9) compound is constructed by analysis of data of its magnetic properties. For Mn_(3.1)Sn_(0.9)N compound, parasitic ferromagnetism exists in the temperature range of 5-370 K, besides a spin-reorientation at about 280 K. Mn_(3.1)Sn_(0.9) compound exhibits a metallic conducting behavior, while Mn_(3.1)Sn_(0.9)N displays a metal-nonmetal transition due to the electron localization caused by the static disorder. The differences of the physical properties between the both compounds, are discussed, in terms of the correlation of the hexagonal DO_(19) and the cubic anti-perovskite structures, the reduction of the distances between Mn atoms, and the spin-pairing or charge transfer effect due to the electron donation by N 2p to Mn 3d states after introduction of N atoms into the interstitial sites of Mn_(3.1)Sn_(0.9) compound.