Abstract: Triacetone triperoxide(TATP) is an easily synthesized explosive. Since the TATP contains no nitro groups and is thermally labile, it is difficult to detect with conventional analytical methods used to determine more established explosives, such as TNT and RDX. In this paper, the calculations were carried out for TATP and its protonated ion using the density functional theory(DFT) method at the B3LYP/cc-pVDZ level. The optimized geometries of TATP and [TATP+H]⁺ were obtained. The proton affinity of TATP is 866.73 kJ/mol based on the calculated total energies of TATP and [TATP+H]⁺. The reaction between H₃O⁺ and TATP were researched in paper with the homemade proton transfer reaction mass spectrometry(PTR-MS). The ion products were found at mass charge ratio of m/z=91, 75, 74, 59, 43 and so on. After reducing the E/N across the drift tube, the protonated TATP ion was found at mass charge ratio of m/z=223. Combined the calculated results, the proposed [TATP+H]⁺ fragmentation pathways were discussed. TATP can be identified exactly and detected rapidly by the change of these characteristic ions, such as m/z=223, 91 and 43. The m/z=43 product ion can be routinely detected at a TATP concentration of about 5.0×10^-10 mol/L(±50%).

Key words: Proton transfer reaction mass spectrometry(PTR-MS), Triacetone triperoxide(TATP), Ion chemistry, Explosive