Antiferromagnetic exchange interaction of Cr3+ dimer in acid erothro chloride [(NH3)5CrOHCr(NH3)4(H2O)]Cl5·H2O and LaAlO3:Cr3+ molecules Original Research Article

The antiferromagnetic phenomena of the chromium(III) dimer in acid erothro chloride [(NH3)5CrOHCr(NH3)4(H2O)]Cl5·H2O and LaAlO3:Cr3+ have been explained in terms of the Girerd–Journaux–Kahn (GJK) model and the Heitler–London (HL) model, respectively. For the Cr⋯Cr distance R in the range the values of the exchange interaction parameter J calculated with the GJK model are higher by a factor 2–3 than those with the HL model. This means that the contribution of the excited charge-transfer configuration (CTC) is considerably important and the main physical mechanism of the antiferromagnetic characteristics in acid erothro chloride and in LaAlO3:Cr3+ can be attributed to the combined effect of the direct exchange and the superexchange interactions.