Enhanced susceptibility in LNiO3 perovskites ( L = La,Pr,Nd,Nd0.5Sm0. 5)
The temperature dependence of the resistivity rho(T) and of the dc magnetic susceptibility chi(T) were measured on high-quality LNiO3 (L = La,Pr,Nd,Nd0.5Sm0.5) samples synthesized under high oxygen pressure. Subtraction of the rare-earth contribution to chi(T) allows the presentation of the evolution of the susceptibility of the NiO3 array from Pauli to Curie-Weiss paramagnetism with decreasing bandwidth. A metal-insulator transition occurring at a temperature T(t) = T(N) is first order for L = Pr and Nd; it becomes second order and produces no anomaly in chi(-1)(T) at a T(t)>T(N) for L = Nd0.5Sm0.5. In the antiferromagnetic domain T<T(N), the chi(T) curve for the NiO3 array resembles that of a paramagnet.
Zhou
J
Texas Materials Institute, ETC 9.102, University of Texas at Austin, Austin, Texas 78712-1063, USA.
Goodenough
JB
Dabrowski
B
Klamut
PW
Bukowski
Z