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The objective of the work presented here is to study the laser-induced decomposition of a condensed HNO3/2-nitropropane mixture containing 58% nitric acid. On the macroscopic scale, this energetic material detonates. Under static high pressure, the formation of an H-bonded complex with that particular composition was demonstrated in a previous study. The high pressure behavior of the complex showed the presence of a solid-solid phase transition around 18 GPa. The combustion front propagation velocity was recorded between 6 and 31 GPa. The analysis of the optical properties of the reaction products as well as the recording of their Raman spectra showed two different combustion regimes. Below 18 GPa, total combustion takes place in the sample and a black residue only composed of soot remains in the cell. Above 18 GPa, the combustion leads to a clear residue with little carbon present. However, the Raman spectra of the remaining sample show new features indicating the presence of species which are not yet clearly identified. The pressure limit between these two behaviors corresponds to the phase transition pressure measured for the complex. [ABSTRACT FROM AUTHOR]

High pressure Raman spectroscopy measurements in a diamond anvil cell (0–50 GPa) on nitric acid (NA), 2-nitropropane (2NP), triethylamine (TEA), diethylamine (DEA) as well as the 2NP/NA, NA/H2O and 2NP/ethylamine mixtures are reported. 2NP/TEA and 2NP/DEA mixtures have also been studied by infrared spectroscopy at ambient pressure. The differences noticed at room pressure between the Raman and infrared spectra of the mixtures and those of the pure compounds are highlighted and discussed. The high pressure decomposition of the 2NP/NA mixture with oxygen balance (O.B.=0) has been observed. The role of the NO2 bonds in the intermolecular interactions in pure compounds and in the mixtures, and the reactivity of the 2NP/NA system is discussed. The influence of water and ethylamines on, respectively, the high pressure behaviour of NA and 2NP have also been studied. Several hypothesis are advanced concerning their sensitizing effect or no on the 2NP/NA mixture. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]