Dynamic observation of a thermally activated structure change in 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) by second harmonic generation
- Los Alamos National Lab., NM (United States)
Using optical second harmonic generation (SHG) the authors observe, for the first time, a structural change in the energetic material (dry-aminated production grade) TATB (1,3,5-triamino-2,4,6-trinitrobenzene) upon heating. This structure change is verified by X-ray powder diffraction (XPD). The kinetics of this structure change are measured and are found to closely match commonly accepted thermal decomposition parameters for the first step, analogous to observations made for the {beta} to {delta} phase transition in HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine). Consequently, these solid structure transitions appear to be coupled to the chemical decomposition mechanism or it may be the first physical process occurring. The authors apply this technique as a diagnostic to an ignition experiment. This experiment demonstrates that the structure change can be rapid (it is thermally activated) and that SHG can be used to indicate not only the solid structure change (large increase in SHG intensity) but also the onset to significant decomposition (subsequent drop in SHG intensity). The ability to selectively change the efficiency of the SHG, in a single piece of explosive, is also demonstrated and may have novel nonlinear optical applications. This application of SHG to TATB constitutes a fundamentally new probe in the dynamics of TATB decomposition, ignition, and combustion and may have application to optical integrated devices for frequency conversion and information encoding.
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 682073
- Journal Information:
- Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical, Vol. 103, Issue 26; Other Information: PBD: 1 Jul 1999
- Country of Publication:
- United States
- Language:
- English
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