magnetic properties 3 molecular magnetism 3 point charges model single ion magnets 3 Journal Article 2 crystal field Hamiltonian 2 Comment 1 mehr ... Letter 1 Research Support, Non-U.S. Gov't 1 coordination chemistry 1 lanthanoids 1 ligand field 1 magnetic anisotropy 1 magnetometry 1 rare earths 1 spin Hamiltonian 1 weniger ...