Two-leg spin ladder model for Ag2VOP2O7 from mapping analysis based on first principles density functional calculations

摘要

The magnetic properties of Ag2VOP2O7 were examined by evaluating its spin exchange interactions in terms of spin dinner analysis based on tight binding calculations and mapping analysis based on first principles density functional theory calculations. Both calculations show that a strong spin exchange interaction occurs through the super-superexchange path J(1) with the V center dot center dot center dot V distance of 5.293 angstrom. This strong anti ferromagnetic interaction forms isolated spin dimer units, which are coupled antiferromagnetically by the spin exchange path J(3) to form a two-leg spin ladder that has no spin frustration. The inter-dimer interaction J(2) is found to be ferromagnetic, and does not lead to spin frustration.