Synthesis, High-resolution Crystal Structure Refinement and Magnetic Properties of the Manganese-rich Cementite-type Mn1.8Fe1.2C

The manganese-rich ternary cementite phase Mn1.8Fe1.2C has been synthesized by a ceramic route in an almost quantitative yield, and the crystal structure refinement on the basis of high-resolution X-ray powder diffraction data using MoKα1 radiation has been performed. The carbon atom is found in a slightly distorted trigonal prism composed of Mn and Fe atoms, with a rather narrow bond length range from 1.95 to 2.09 Å. The magnetic susceptibility data clearly indicate long-range ordering phenomena, in particular dominant antiferromagnetic interactions, as predicted by density-functional theory.