Uniaxial antiferromagnetic ordering in HoFe2Ge2: a neutron and magnetic study

The magnetic structure of the compound HoFe2Ge2 (I4/mmm S.G) has been studi ed by neutron diffraction, magnetic and specific-heat measurements. The par amagnetic neutron data confirmed the ThCr2Si2 type of structure reported ea rlier for this compound. The analysis of the data collected in the magnetic ally ordered regime (T-N = 17 K) showed a uniaxial arrangement of the Ho mo ments along c associated with the wave vector q = (1/2,1/2,0). The moments of the atoms related by the non-primitive translation (1/2,1/2,1/2) are ant iparallel. The refined moment value at 1.5 K is mu(Ho)=6.6(1) mu(B). In add ition to the ordered phase the neutron data comprise diffuse magnetic peaks in the low-angle region demonstrating the coexistence of short-range order effects below 6 K. (C) 1999 Elsevier Science S.A. All rights reserved.