Charting Regions of\nCobalt’s Chemical Space\nwith Maximally Large Magnetic Anisotropy: A Computational High-Throughput\nStudy

Magnetic anisotropy slows down magnetic relaxation and\nplays a\nprominent role in the design of permanent magnets. Coordination compounds\nof Co(II) in particular exhibit large magnetic anisotropy in the presence\nof low-coordination environments and have been used as single-molecule\nmagnet prototypes. However, only a limited sampling of cobalt’s\nvast chemical space has been performed, potentially obscuring alternative\nchemical routes toward large magnetic anisotropy. Here we perform\na computational high-throughput exploration of Co(II)’s chemical\nspace in search of new single-molecule magnets. We automatically assemble\na diverse set of ∼15,000 novel complexes of Co(II) and fully\ncharacterize them with multireference ab initio methods. More than\n100 compounds exhibit magnetic anisotropy comparable to or larger\nthan leading known compounds. The analysis of these results shows\nthat compounds with record-breaking magnetic anisotropy can also be\nachieved with coordination four or higher, going beyond the established\nparadigm of two-coordinated linear complexes.