Powder diffraction data and Rietveld refinement of Hägg-carbide, χ-Fe5C2

The structure and powder diffraction data of Hägg-carbide (χ- Fe 5 C 2 ) have been redetermined and improved by X-ray diffraction. Experimental values of 2θ, corrected for systematic errors, relative peak intensities, lattice spacings, and the Miller indices of 27 observed reflections up to 100° 2θ are reported. The unit cell is monoclinic (space group C 2/ c , Z =4) with a =11.588 Å, b =4.579 Å, c =5.059 Å, and β=97.75°. The crystal structure has been refined by Rietveld analysis, resulting in R wp =0.073.