Hopkinson-like effect in single-crystalline CdCr 2Se 4 and Cd[Cr 1.89Ti 0.08]Se 4

The static (dc) and dynamic (ac) magnetic measurements of CdCr2Se4 and Cd[Cr1:89Ti0:08]Se4 showed their ferromagnetic properties with a Curie temperature TC 130 K and revealed on the real component of ac susceptibility curve, the peaks near TC at 200 Oe, 450 Oe and 1 kOe, characteristic for the Hopkinson ones. The meaningful reduction of saturation moment to 4.73 B/f.u. for Cd[Cr1:89Ti0:08]Se4 suggests the diamagnetic con guration of Ti ions, which dilutes the ferromagnetic sublattice of Cr ones and causes reducing of the energy losses visible on the imaginary components of ac susceptibility curve. Close for zero values of higher susceptibility harmonics above TC are pointing out to the lack of the spin uctuations in the paramagnetic state