Eur. Phys. J. B 23, 29-36 (2001)
https://doi.org/10.1007/s100510170079

Magnetic structure and anisotropy of YFe₆Ga₆ and HoFe₆Ga₆

¹ INFM, Dipartimento di Fisica, Università di Modena e Reggio Emilia, Via G. Campi 213/a, Modena, 41100, Italy
² School of Physics, University of NSW, Sydney, 2052, Australia
³ Van der Waals-Zeeman Institut, Universteit van Amsterdam, Valckenierstraat 65, 1018 XE, Amsterdam, The Netherlands
⁴ Neutron Scattering Group, Australian Institute of Nuclear Science and Engineering, Menai, NSW, 2234, Australia

Corresponding author: ^a moze.oscar@unimo.it

Received: 8 March 2001
Revised: 18 June 2001
Published online: 15 September 2001

Abstract

The magnetic structure of RFe₆Ga₆ intermetallic compounds with R = Y, Ho have been determined by neutron powder diffraction, ⁵⁷Fe Mössbauer spectroscopy, AC susceptibility, TGA (Thermo-Gravimetric Analysis) and magnetization measurements. Both compounds crystallize in the tetragonal ThMn₁₂ structure (space group I4/mmm) with the magnetic structure of YFe₆Ga₆ consisting of a simple ferromagnetic alignment of Fe moments in the basal plane with a Curie temperature of 475(5) K. Gallium atoms are found to fully occupy the 8i site, with Fe and Ga atoms equally distributed over the 8j site, whilst Fe atoms fully occupy the 8f site. The average Fe moments are 1.68(10) µB and 1.46(10) µB at 15 and 293 K, respectively. The average room temperature Fe magnetic moments determined by neutron diffraction are in overall agreement with the average Fe moment deduced from Mössbauer spectroscopy and bulk magnetization measurements on this compound. The magnetic anisotropy of the compound HoFe₆Ga₆ is also planar in the temperature range 6-290 K, with Ho magnetic moments of 9.28(20) µB and 2.50(20) µB at 6 K and 290 K, respectively, coupled anti-ferromagnetically to the Fe sublattice and a Curie temperature of 460(10) K. The magneto-crystalline anisotropies of both compounds are comparable at low temperatures.