Abstract
(Chemical Equation Presented) DFT calculations have identified the novel rearrangement shown here for decomposition of the Si derivative of the PETN explosive [PentaErythritol TetraNitrate (PETN), C(CH2ONO 2)4] that explains the very dramatic increase in sensitivity observed experimentally. The critical difference is that Si-PETN allows a favorable five-coordinate transition state in which the new Si?O and C?O bonds form simultaneously, leading to a transition state barrier of 33 kcal/mol (it is 80 kcal/mol for PETN) and much lower than the normal O?NO 2 bond fission observed in other energetic materials (∼40 kcal/mol). In addition this new mechanism is very exothermic (45 kcal/mol) leading to a large net energy release at the very early stages of Si-PETN decomposition that facilitates a rapid temperature increase and expansion of the reaction zone.
Original language | English (US) |
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Pages (from-to) | 7490-7491 |
Number of pages | 2 |
Journal | Journal of the American Chemical Society |
Volume | 131 |
Issue number | 22 |
DOIs | |
State | Published - Jun 10 2009 |