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Abstract — A kinetic dual shutter ion mobility spectrometer with a gas chromatograph as a sample pre-fractionation inlet was built to determine ion lifetimes, energies, and kinetics of decomposition of gas phase ions of energetic materials. Measurements of thermal dissociation of chloride adducts of explosives, namely nitroglycerine (NG), ethylene glycol dinitrate (EGDN) and dimethyl nitro butane (DMNB) ions in negative mode, were selected for study, fi rst owing to known sensitivity to thermal dissociation. The dissociations of EGDN·Cl ˉ and NG·Cl ˉ were observed in the temperature ranges of 79 to 97 oC and 111 to 122 oC at ambient pressure. The only decomposition path was the displacement of NO3 from Cl: NG·Cl ˉ → [NG-NO3+Cl] + Cl ˉ and EGDN·Cl ˉ → [EGDN-NO3+Cl] + Clˉ. The rate constants determined over the temperature ranges yielded activation energies for the dissociations of NG·Cl ˉ and EGDN.Cl- were 80 ± 3 kJ mol-1 and 59 ± 1 kJ mol-1. The dissociation of DMNB·Cl ˉ was observed in the temperature range of 69 to 84 oC. The decomposition path was determined to be the loss of Cl: DMNB·Cl ˉ → DMNB + Clˉ. The activation energy for the dissocia-tion of DMNB·Cl ˉ was 67 ± 2 kJ mol-1. Ab-initio calculations at the 6-311+G(dp) level were used to validate the experimentally obtained kinetic data and the reaction paths