Comparative Study of n-C5 Bond Dissociation Energies and H-Atom Abstraction via H for Alkane, Alcohol, Methyl Ether, Nitroso, Nitro, Nitrite, and Nitrate.

Abstract

Energetic materials have a wide range of applications, for many of which new materials are constantly developed. For understanding how energetic materials are chemically converted, it is essential to systematically understand how relevant functional groups affect the stability and properties of such materials. Here, the impact of nitroso, nitro, nitrite, and nitrate functional groups on a pentyl moiety is studied theoretically, focusing on bond dissociation energies and H atom abstraction via Ḣ. The nitroso group is found to imply the strongest effects, while the nitro group appears to exert a stabilizing effect on the pentyl moiety. Importantly, the nitrogenated functional groups generally stabilize the pentyl moiety, in contrast to alcohol and methyl ether functional groups. Therefore, it is concluded that using analogies to the chemistries of the latter two functional groups for chemical kinetic modeling of nitrogenated functional groups is not adequate. Based on the presented bond dissociation energies and rate coefficients, it is to be expected that unimolecular bond fissions at the nitrogenated functional groups will dominate over a wide temperature range. Building on the provided data, future detailed chemical kinetic modeling efforts for nitroso, nitro, nitrite, and nitrate compounds can be aided or initiated.