Optical property and spectroscopy studies on the explosive 2,4,6-trinitro-1,3,5-trihydroxybenzene in the terahertz range

Using the terahertz time-domain spectroscopy, the complex refraction index and dielectric function of the pure 2,4,6-trinitro-1,3,5-trihydroxybenzene (TNPG) are calculated with the obtained parameters of the pure polyethylene (PE) and a mixture of TNPG and PE based on the Bruggeman effective medium theory. The theoretical investigation consistent with the experimental data in the vibration spectra of TNPG is presented in the range of 0.2-2.5 THz. The results reveal that the two absorption features identified as the fingerprint of TNPG in our studied range are mainly dominated by the intramolecular collective vibration modes. (C) 2008 American Institute of Physics.