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CF₂Cl₂ has been found to react with nanoscale MgO at 325 °C and higher temperatures. In excess of the halocarbon, the reaction results in the formation of MgF₂ as a predominant solid product, with CCl₄, and CO₂ formed as the main gaseous products. The kinetics of the process is characterized by a prolonged induction period, which is as long as 8.5 h at 325 °C. The length of the induction period decreases with temperature increase and becomes negligible at 500 °C. Complete CF₂Cl₂ mineralization has been achieved in an excess of MgO at 450 °C. Detailed HRTEM and EDX analysis has shown that the induction period involves the formation of small amounts of magnesium halides on the oxide surface and results in its reconstruction leading to initial oriental ordering of the nanocrystals followed by substantial changes in the bulk composition of the nanoparticles. The reaction proved to be structurally …