The DFT rationalization of exchange and anisotropy in one-dimensional d-p magnets: The [MnIII(porphyrin)][TCNE] case study

We report here numerical experiments, modeling and interpretations dealing with the magnetic interactions necessary for building nano-scale magnets in quasi-one-dimensional systems based on the assembling of [Mn(porphyrin)]+ magnetically anisotropic d units and TCNE-p-type spin carriers. The magnetic ordering and its coupling parameter are studied by Broken Symmetry DFT calculations for various model structures, allowing for the rationalization of geometry dependence of the effective exchange. The roles of the phenyl substituent, as well as of the basis set and the DFT functional used in the computation are discussed. The intrinsic anisotropy of these systems is studied in an original manner, extracting Ligand Field and Spin Orbit parameters by combined fits to non-relativistic and relativistic DFT calculations, allowing the explicit estimation of the Zero Field Splitting parameters.

Graphical abstractWe report numerical experiments and modeling of [Mn(porphyrin)]+[TCNE]− quasi-one-dimensional magnets. Broken Symmetry DFT calculations reveal the geometry dependence of the effective exchange coupling. The intrinsic anisotropy of these systems is studied in an original manner, extracting Ligand Field and Spin Orbit parameters by combined fits to non-relativistic and relativistic DFT calculations.Figure optionsDownload full-size imageDownload as PowerPoint slide