Dinuclear manganese, iron, chromium, and cobalt complexes derived from aroylhydrazone ligands: Synthetic strategies, crystal structures, and magnetic properties

•Synthetic strategies employed to obtain new and magnetically interesting dinuclear molecules based on iron, manganese, chromium, and cobalt metal ions.•Compared crystal structures of 15 dinuclear complexes.•Very strong ferromagnetic interactions in Mn3+ dinuclear compounds.•Magnetostructural correlations discussed.•Compared data from theoretical calculations.