Below is a paper that was written a number of years ago been and is still of interest
The very far-infrared spectra of energetic materials and possible confusion materials using terahertz pulsed spectroscopy
Vibrational Spectroscopy 42(2)243-248(2006).
T. Lo, I.S. Gregory, C. Baker, P.F. Taday, W.R. Tribe, M.C. Kemp
The full paper can be found at http://www.sciencedirect.com/science/article/pii/S0924203106000439
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