Magnetism: Molecules to Build Solids

The seminal discovery in 1981 of bimetallic ferrimagnetic chains, based on the synthetic use of the concept “complex as ligand”, can be considered as a significant step on the way from molecules to more and more complex materials. We describe the chemistry, the structures, the magnetic properties of these 1D materials, together with the new theoretical models created to understand them. We then give an overview of some original creative ideas, which have irrigated the synthetic chemistry of brand‐new molecular materials, room temperature magnets, photomagnetic and chiral magnets or functional surfaces. The review emphasizes that the celebrated individual “wins” are indeed the fruit, along the years, of the constructive multidisciplinary collaboration of many scientists, theoreticians and experimentalists, chemists and physicists. Difficulties, dead‐end hypotheses, mistakes which represent a significant exciting part of any scientific endeavour, are not put under the rug.