Magnetocaloric Efficiency Tuning Through Solvent-Triggered 3D to 2D Interconversion in Holmium(iii)-Based Dynamic MOFs

The neutral holmium(iii) oxalate octadecahydrate {[Ho2(ox)3(H2O)6]·12H2O}n of mixed hexagonal/decagonal (63·103) 3D net topology shows important changes in the magnetocaloric efficiency upon dehydration/rehydration by heating and water vapor exposition to give the holmium(iii) oxalate decahydrate {[Ho2(ox)3(H2O)6]·4H2O}n of hexagonal (63) 2D net topology through the intermediacy of the elusive amorphous anhydrous compound {Ho2(ox)3}n.