Magnetovolume effects in Ce2Fe17 compound

The magnetic susceptibility, electric resistivity and thermal expansion of the polycrystalline intermetallic compound Ce2Fe17 were studied under hydrostatic pressures up to 10 kbar at temperatures from 10 K to 300 K. At ambient pressure the compound is a noncollinear ferromagnet below Theta (T) = 94 K and an antiferromagnet for Theta (T) < T < T-N, T-N = 206 K. The temperatures of magnetic transitions are well pronounced as anomalies on the magnetic susceptibility, electric resistivity and thermal expansion temperature dependencies. The giant negative pressure effect on Theta (T) was determined: d Theta (T)/dP = - (38 +/- 2) K/kbar. The ferromagnetic state is suppressed by pressure of P-C = 2.5 kbar. The pressure effect on the Neel temperature T-N = 206 K is significantly smaller: dT(N)/dP = - (1.7 +/- 0.2) K/kbar. The large positive spontaneous volume magnetostriction observed below T-N is suppressed by application of high pressure and disappears for P > P-C. The initial volume compressibility in magnetically ordered states increases four times in comparison to the paramagnetic state. The results show a strong correlation between magnetic proper-ties and the lattice volume, Possible competition of positive and negative exchange interactions between iron atoms and/or valence instability of Ce can be considered as reasons for such correlation.