It was shown experimentally that the magnetocaloric properties of molecule-based Prussian blue analogues could be adjusted by controlling the number of intrinsic vacancies during synthesis. For CsxNi4II[CrIII(CN)6](8+x)/3, it was indeed found that the ferromagnetic phase transition induced significant magnetic entropy changes, whose maxima shifted from ≈68 to ≈95K upon varying the number of [CrIII(CN)6]3- vacancies. This offered the possibility of tuning  the magnetocaloric effect in this complex.

Vacancy-Driven Magnetocaloric Effect in Prussian Blue Analogues. M.Evangelisti, E.Manuel, M.Affronte, M.Okubo, C.Train, M.Verdaguer: Journal of Magnetism and Magnetic Materials, 2007, 316[2], e569-71