Using a combined approach of DFT calculations, XAS studies, and PDF analysis, we have demonstrated that RHT induces significant distortions in the {Zr 6 } cluster within the Zr-based MOF, DUT-67. These distortions, driven by thermally induced dehydration of the clusters, create O-vacancies and reduce the valency of Zr, leading to a remarkable enhancement in catalytic performance. Moreover, TEM, WT-EXAFS, and PDF analysis all confirm that even after MOF amorphization during RHT, the porous aDUT-67 phase retains discrete, interconnected {Zr 6 } clusters.