Ma Teng, Yin Yunyu, Hong Fang, Zhu Pinwen, Yu Xiaohui
State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China.
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics Chinese Academy of Sciences, Beijing 100190, China.
ACS Omega. 2021 May 8;6(19):12591-12597. doi: 10.1021/acsomega.1c00551. eCollection 2021 May 18.
We sintered bulk trigonal ε-FeN (space group: 312) with the high-pressure and high-temperature method. Structural refinements by the Rietveld method result in a trigonal unit cell with parameters of = 4.7767(1) Å and = 4.4179(3) Å. ε-FeN is ferromagnetic with a Curie temperature of ∼250 K, a saturation magnetization ( ) value of up to 1.2 μ/formula units (f.u.), and comparatively low coercive field. The Vickers hardness was measured, and the results showed that the asymptotic hardness of bulk ε-FeN is about 6.5 GPa with a load of 1000 g. Thermogravimetric (TG) analysis shows that ε-FeN is thermally stable below 670 K. ε-FeN exhibits good metal conductivity, and the electron transport measurements show that the resistivity of it is 172 μΩ cm at room temperature. The theoretical calculations suggest that the conducting states are mainly derive from Fe-3d states.
我们采用高压高温法烧结了块状三方ε-FeN（空间群：312）。通过Rietveld方法进行结构精修，得到了一个三方晶胞，其参数为 = 4.7767(1) Å和 = 4.4179(3) Å。ε-FeN是铁磁性的，居里温度约为250 K，饱和磁化强度（ ）值高达1.2 μ/化学式单位（f.u.），且矫顽场相对较低。测量了维氏硬度，结果表明，在1000 g载荷下，块状ε-FeN的渐近硬度约为6.5 GPa。热重（TG）分析表明，ε-FeN在670 K以下热稳定。ε-FeN表现出良好的金属导电性，电子输运测量表明，其在室温下的电阻率为172 μΩ cm。理论计算表明，导电态主要源于Fe-3d态。
