Magnetic excitations in transition metal and rare earth metal dimers

Abstract

Inelastic neutron scattering is a powerful technique for the study of exchange interactions in transition metal and rare-earth metal clusters. In the classical dinuclear acid rhodo chromium(III) complex, [(ND₃)₅CrODCr(ND₃)₅] Cl₅ • D₂O, the antiferromagnetic exchange parameter was found to decrease by 5–10 percent between 45K and 290K. In both Cs₃Yb₂Cl₉ and Cs₃Yb₂Br₉, the exchange coupling is best described by a Heisenberg model with 2J – 0.40 and 0.37 meV, respectively. In the mixed dimer YbCrBr₉ ^3-, the observed Q dependence clearly shows the presence of anisotropy.