~(119)Sn Moessbauer spectroscopy investigation of Nd_3Cu_4Sn_4, Nd_3Ag_4Sn_4, and Ho_3Cu_4Sn_4

摘要

Nd_3Cu_4Sn_4, Nd_3Ag_4Sn_4, and Ho_3Cu_4Sn_4 have been studied using ~(119)Sn Moessbauer spectroscopy. Contrary to recent neutron diffraction data, Nd_3Cu_4Sn_4 shows a clear magnetic signal at 1.6 K and has an ordering temperature of 2.0(1) K. Nd_3Ag_4Sn_4 orders at 4.8(1) K, in agreement with neutron diffraction measurements. We observe the ordering of the Ho 2d sublattice in Ho_3Cu_4Sn_4 at 8.2(1) K but we also see some residual magnetic splitting up to 10.5(2) K, which was not previously detected by neutron scattering.