title: Exchange interaction in the insulating phase of RNiO3.
abstract: In order to characterize the spin-spin exchange interactions responsible for the Type-E' antiferromagnetic order in inhomogeneous RNiO3 perovskites (R=Y or rare earth), the pressure dependence of the Néel temperature T(N) was systematically measured for samples with T(N)<T(IM) and T(N)=T(IM); T(IM) is an insulator-metal transition temperature. Analysis of the results shows that, as for superexchange, perturbation theory can be used to describe the interatomic exchange interactions for T(N)<T(IM), but the perturbation theory breaks down where T(N) approaches T(IM).
authors.affiliation: Texas Materials Institute, University of Texas at Austin, 1 University Station, C2201, Austin, Texas 78712, USA.
authors.forename: J-S
authors.initials: JS
authors.lastname: Zhou
authors.forename: J B
authors.initials: JB
authors.lastname: Goodenough
authors.forename: B
authors.initials: B
authors.lastname: Dabrowski