Discrete {(Gd4M)-M-III} (M = Gd-III or Co-II) pentanuclear complexes: a new class of metal-organophosphate molecular coolers

The first examples of homo- and hetero-polymetallic organophosphates of gadolinium are reported. Magnetic measurements reveal a higher magnetic entropy change for the isotropic {Gd-5(III)} complex (25.8 J kg(-1) K-1) as compared to the heterometallic {(Gd4CoII)-Co-III} complex (20.3 J kg(-1) K-1), which is attributable to a change in magnetic coupling as estimated from DFT calculations