title: Study of acoustic fingerprinting of nitromethane and some triazole derivatives using UV 266 nm pulsed photoacoustic pyrolysis technique.
abstract: We report a comparative study of acoustic fingerprints of nitromethane, nitrobenzene and some nitro rich triazole derivatives using pulsed photoacoustic technique. UV 266 nm wavelength i.e. Fourth harmonic of Q-switched Nd: YAG laser having pulse duration 7 ns and 10 Hz repetition rate is employed to record the time resolved PA spectrum. The PA fingerprint is produced due to absorption of incident UV light by molecule itself and photo dissociation of nitromethane and nitrobenzene at room temperature while in case of triazole it is attributed to the combination of thermal and photo-dissociation process. The entire dissociation process follows the root of cleavage of C-NO₂ bond to produce free NO, NO₂ and other by product gases due to π(∗)←n excitation. In addition, we have studied the thermal stability criteria of nitro rich triazoles based on the quality factor of acoustic resonance frequencies of the PA cavity. We have also studied the effect of data acquisition time to ascertain the decay behavior of HEMs samples.
authors: Advanced Center of Research in High Energy Materials (ACRHEM), University of Hyderabad, Hyderabad 500046, India.
authors: K S
authors: KS
authors: Rao
authors: Advanced Center of Research in High Energy Materials (ACRHEM), University of Hyderabad, Hyderabad 500046, India. Electronic address: akcphys@gmail.com.
authors: A K
authors: AK
authors: Chaudhary
authors: Department of Mathematics and Physics, Faculty of Education, Al-Baida University, Al-Baida 38018, Yemen.
authors: F
authors: F
authors: Yehya
authors: Advanced Center of Research in High Energy Materials (ACRHEM), University of Hyderabad, Hyderabad 500046, India.
authors: A Sudheer
authors: AS
authors: Kumar
keywords: Fingerprint; Nitrobenzene; Nitromethane; Photoacoustic; Triazoles; UV 266nm