The effect of a replacing La by Ce in Gd_{0.9}La_{0.1}Cu_{6} was investigated by ESR method. It was found that cerium ions cause an increase in the conduction electron relaxation to the lattice and change the conduction electron band structure.
The lattice parameters a and c of CeM_{2}Sn_{2} show an anomalous temperature dependence compared to the analogous variations for LaM_{2}Sn_{2}. The anomaly Δa of thermal expansion for CeCu_{2}Sn_{2} has a maximum around 90 K, whereas Δc has a maximum near 140 K, near to the maximum of the magnetic resistivity Δρ.
The magnetic specific heat of GdNi_{2}Sn_{2}, GdNi_{2}Sb_{2} and GdCu_{2}Sb_{2} shows a λ-type anomaly at T_{N} with a noticeable reduction of the discontinuity compared to that expected for a simple antiferromagnet. It can be associated with the existence of amplitude modulated magnetic structure just below T_{N}. Above T_{N} a weak magnetic contribution is observed, evidencing the short-range ordering. From neutron diffraction studies it can be also concluded that investigated compounds have not simple antiferromagnetic structures. For GdNi_{2}Sn_{2} the propagation vector Q=(0.3,1/2,1/2) was found with the magnetic moments along the [1,0,0] axis.