X-ray powder diffraction data and structural study of Fe_2GeSe_4

摘要

The room temperature X-ray powder diffraction pattern of Fe_2GeSe_4, a Ⅱ_2 □ Ⅳ Ⅵ_4 semiconducting compound, has been recorded and evaluated. This material was found to be orthorhombic, a=13.069(1), b=7.559(1), c=6.2037(6)A, V=612.83(9) A~3, Z=4, D_x =5.42 g cm~-3. The structure refinement carried out using the Rietveld method indicated that this material crystallizes in space group Pnma (No. 62) with an olivine type of structure. The refinement of 33 parameters led to R_wp=15.3/100, R_10.2/100 for 5251 step intensities and R_B=9.44/100 and R_F=9.36/100 for 913 reflections.