Study of thermal decomposition mechanisms and absorption cross section of nitro-rich phenyl- and bis-series 1,2,3-triazoles.

This paper reports the investigation of thermal decomposition mechanisms and evaluation of thermally released NO2 from two newly synthesized high-energymaterials named 1-(4-nitrophenyl)-1H-1,2,3-triazole (S-8) and 2,6-bis ((4-(nitromethyl)-1H-1,2,3-triazol-1-yl) methyl) pyridine (S-9) using time-resolved pulsed photoacoustic (PA) pyrolysis technique. The PA spectra were recorded between the 30 degrees C and 350 degrees C range and by varying the pressure of compounds vapor using 532 nm wavelength of pulse duration 7 ns at 10 Hz repetition rate obtained from Q-switched Nd:YAG laser pulses. The PA results were cross verified with thermogravimetric-differential thermal analysis data. The quality factor "&=&Q"&=& of the PA cavity was measured to test the thermal stability of the compound. In addition, we have ascertained the molecular density, absorption cross sections of high-energy materials vapor in terms of NO2. The corresponding values are of the order of 0.1-1.2 x 10(20) cm(-3) and 0.5-6 kilobarn, respectively. These results once again confirm the close agreement between the radiative and nonradiative transitions data and established the role of NO2 during the thermal decomposition process. (C) 2016 Optical Society of America