DFT Study of the Cr-8 Molecular Magnet Within Chain-Model Approximations

We present a density functional theory (DFT) study of the electronic and magnetic properties of the Cr-8 molecular ring. The all-electron linearized augmented plane wave method (LAPW) implemented in the Wien2k package and pseudopotential method implemented in SIESTA package are used to calculate the electronic states, exchange coupling parameters of an infinite chain model system of Cr-8. We demonstrate how, under opportune modifications to the ring cycle structure, different one-dimensional chain models can be devised, with the capability of mimicking with good approximation the electronic and magnetic properties of the original Cr-8 molecule. Such models offer an unique opportunity, in virtue of the reduced computational effort, to carry out extensive investigations of a whole set of molecules belonging to the Cr-based molecular rings family.