The large cryogenic magnetocaloric effect of a 3D oxydiacetate-bridged gadolinium–manganese MOF material, [Mn(H2O)6][MnGd(oda)3]2·6H2O (1), was evaluated by magnetization and heat capacity measurements. A maximum −ΔSm of 50.1 J kg−1 K−1 for ΔH = 70 kG along with significant entropy change at lower field was found on account of the weak Mn⋯Gd ferromagnetic interactions and the small molecular mass. This suggests that 1 could be considered as a potential coolant for liquid helium temperature applications.
