Pressure dependence of the Néel temperature in NdMn2 and related compounds
Resistivity measurements on Nd(Mn1 - xCux)2 compounds in the temperature range from 4.2 to 300 K show that magnetic order disappears for x exceeding 0.07. In order to investigate the role of the lattice parameter in the suppression of magnetic order, the effect of pressure on the Néel temperature has been studied by performing resistivity measurements under pressures up to 5 kbar. A linear decrease with pressure has been found with dTN/dp values of -3.45 K/kbar, -2.76 K/kbar and -1.59 K/kbar for the compounds with x = 0, 0.03 and 0.05, respectively. From a comparison with the effect of chemical pressure observed in (Nd, Lu)Mn2 compounds, it is concluded that the lattice parameter is not the (only) decisive factor, but that the disturbance of the Mn-Mn interaction (caused by substitution of Mn sites) plays an important role. © 1992.