Ultrafast Raman Spectroscopy of Shock Fronts in Molecular Solids
1997; American Physical Society; Volume: 78; Issue: 24 Linguagem: Inglês
10.1103/physrevlett.78.4585
ISSN1092-0145
AutoresG. Tas, Jens Franken, Selezion A. Hambir, David E. Hare, Dana D. Dlott,
Tópico(s)Fullerene Chemistry and Applications
ResumoThe passage of a 4 GPa shock front through an embedded optical nanogauge, a thin $(\ensuremath{\sim}700\mathrm{nm})$ layer of polycrystalline molecular material (anthracene), is monitored in real time by picosecond coherent Raman scattering. Analysis of high resolution Raman spectra shows the shock rise time is less than 25 ps, and the front is less than 100 molecules wide. The rise time is faster than relaxation of nonequilibrium populations of molecular vibrations, which shows a shock front in a molecular material can leave highly nonequilibrium vibrational states in its wake. The implications for shock initiation of energetic materials, typically polycrystalline molecular solids, are briefly discussed.
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