Many-Body Models for Molecular Nanomagnets

We present a flexible and effective ab initio scheme to build many-body models for molecular nanomagnets, and to calculate magnetic exchange couplings and zero-field splittings. It is based on using localized Foster-Boys orbitals as a one-electron basis. We apply this scheme to three paradigmatic systems, the antiferromagnetic rings Cr-8 and Cr7Ni, and the single-molecule magnet Fe-4. In all cases we identify the essential magnetic interactions and find excellent agreement with experiments. DOI: 10.1103/PhysRevLett.110.157204