Magnetic structures in TmPdIn and TmAgSn

•Magnetic structures of TmPdIn and TmAgSn are reported for the first time.•The magnetic structures are verified by group theory symmetry analysis.•The results are compared with those for other TmTX intermetallics.

Low temperature antiferromagnetic structures of TmPdIn and TmAgSn have been derived from powder neutron diffraction data. The magnetic structure of TmPdIn is a commensurate one and related to a propagation vector k→=[13,13,12] while the incommensurate sine-modulated structure of TmAgSn is connected with k→=[kx,−kx,0] where kx = 0.1314(2). The thulium magnetic moments are constrained within the basal plane and show ‘triangular’ arrangement. Validity of obtained magnetic structures is discussed on the basis of symmetry analysis.