Determination of the magnetic structure of Gd2Fe2Si2C by Mössbauer spectroscopy and neutron diffraction.

We have determined the magnetic structure of the intermetallic compound Gd2Fe2Si2C using neutron powder diffraction, (155)Gd and (57)Fe Mössbauer spectroscopy. This compound crystallizes in a monoclinic (C2/m) structure and its magnetic structure is characterized by antiferromagnetic order of the Gd sublattice along the b-axis, with cell-doubling along the c-axis. The propagation vector is k = [0 0 ½]. At 3.6 K the Gd moment reaches 6.2(2) µ(B). Finally, (57)Fe Mössbauer spectroscopy shows no evidence of magnetic ordering of the Fe sublattice.