Structural, magnetic and magnetoelectric properties of Co2Fe2Ta2O9, a TN=53 K honeycomb antiferromagnet

This is the authors' abstract. We don't add key points for this paper.

The bimetallic oxides of general M4M’2O9 formula, where M=Fe, Co, Mn and M’=Nb or Ta, form a family of linear magnetoelectric materials, for which properties depend on the nature of the M,M’ pair. In the present study, the structural, magnetic and magnetoelectric properties of a new member, Co2Fe2Ta2O9, synthesized in polycrystalline form, are reported. This compound crystallizing in the P‐3c1 trigonal ‘429’ structure (a=5.2009 (1) Å, c=14.1986(1) Å and V=332.613(2) Å3) is found to be antiferromagnetic below TN=53 K. Although the structural features are intermediate between the Co4Ta2O9 and Fe4Ta2O9 limit members, a very different magnetoelectric behaviour is observed. In order to reveal the differences between M4M’2O9 with M=Fe or Co or mixed and M’=Ta or Nb, a comparison between these six compounds is proposed.