Explosive phenomena in heavily irradiated NaCl

In heavily irradiated NaCl crystals explosive phenomena can be initiated during irradiation or afterwards when samples are heated to temperatures between 100 and 250 degrees C. During irradiation of NaCl Na and Cl-2 precipitates and void structures are produced along with the accumulation of stored energy (maximum value today similar to 76 kJ/mol, or 18.5% of the enthalpy of formation of NaCl, -411.2 kJ/mol). It is proposed that the collapse of large voids initiate the explosive release of stored energy, giving rise to a localized hot spot and a thermal shock wave. We discuss the nature of these explosive phenomena and show that a basically stable insulating material, such as NaCl may become very unstable after subjecting them to high doses of ionizing radiation