Cryogenic Magnetocaloric Effect in a Ferromagnetic Molecular Dimer

Molecoolers: An unprecedentedly large cryogenic magnetocaloric effect is observed in gadolinium acetate tetrahydrate (see picture, Gd pink, O red, C gray). The change in its magnetic entropy is ascribed to the high magnetic density combined with dominant ferromagnetism. For the first time in a molecular complex, direct measurements of the magnetocaloric effect corroborate indirect estimates based on heat capacity and magnetization.