title: Exploring the sources of the magnetic anisotropy in a family of cyanide-bridged Ni9Mo6 and Ni9W6 systems: a density functional theory study.
abstract: A density functional theory (DFT) study of the magnetic coupling interactions and magnetic anisotropy in a family of experimentally synthesized Ni(9)Mo(V) and Ni(9)W(V) systems is presented. Our calculations show that for all of our selected Ni(9)M(6) systems, the intramolecular magnetic coupling interactions are ferromagnetic, and the ground-state spins are 12. All of the D values of Ni(9)W(6) systems come mainly from the contribution of the D(i) of W(6)(CN)(48)Ni extracted from Ni(9)W(6), and the influence of the eight surrounding Ni including the ligands on their magnetic anisotropy is very small. Although the surrounding Ni bounded by different ligands have a small influence on all D values for our selected complexes, they decide on the core structures of W(6)(CN)(48)Ni, which dominate their magnetic anisotropy. Thus, to obtain a Ni(9)W(6) system having a large negative D, we can use different ligands bound to Ni to obtain a good core structure of W(6)(CN)(48)Ni with a large negative D value. All D values of Ni(9)Mo(6) systems also come mainly from the contribution of D(i) of the Mo(6)(CN)(48)Ni, which is positive or negative but very small; most of these systems do not behave as single-molecule magnets.
authors.affiliation: School of Physical Science and Technology, Nanjing Normal University, Nanjing 210046, China. zhangyiquan@njnu.edu.cn
authors.forename: Yi-Quan
authors.initials: YQ
authors.lastname: Zhang
authors.forename: Cheng-Lin
authors.initials: CL
authors.lastname: Luo