title: Magnetic exchange couplings in the single-molecule magnet of Mn(12)-Ac.
abstract: Four types of isotropic exchange interactions of Mn(12)-Ac are obtained by using the classical Monte Carlo simulations. The equilibrium susceptibilities are well reproduced in the temperature range between 10 and 100 K. The calculated effective spin at 0.1 K coincides with the ground-state spin. Our results show that J(1) and J(2) are strong antiferromagnetic, but the magnitude of J(2) is much smaller than that of J(1). Both J(3) and J(4) favor weakly antiferromagnetic couplings. The effects of the exchange couplings on the magnetic properties and ground-state spin are investigated too. The magnetic susceptibilities below 100 K depend more on J(2) rather than on the stronger J(1). The weak exchange couplings J(3) and J(4) have significant frustration effects on the ground-state configuration.
authors.affiliation: State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, PR China. jrzhang@aphy.iphy.ac.cn
authors.forename: Junrong
authors.initials: J
authors.lastname: Zhang
authors.forename: Lunhua
authors.initials: L
authors.lastname: He
authors.forename: Huibo
authors.initials: H
authors.lastname: Cao
authors.forename: Fangwei
authors.initials: F
authors.lastname: Wang
authors.forename: Panlin
authors.initials: P
authors.lastname: Zhang