Cluster Evolution at Early Stages of 1,3,5-Triamino-2,4,6-trinitrobenzene under Various Heating Conditions: A Molecular Reactive Force Field Study

Abstract

We carried out reactive molecular dynamics simulations by ReaxFF to study the initial events of an insensitive high explosive 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) against various thermal stimuli including constant-temperature heating, programmed heating, and adiabatic heating to simulate TATB suffering from accidental heating in reality. Cluster evolution at the early stage of the thermal decomposition of condensed TATB was the main focus as cluster formation primarily occurs when TATB is heated. The results show that cluster formation is the balance of the competition of intermolecular collision and molecular decomposition of TATB, that is, an appropriate temperature and certain duration are required for cluster formation and preservation. The temperature in the range of 2000-3000 K was found to be optimum for fast formation and a period of preservation. Besides, the intra- and intermolecular H transfers are always favorable, whereas the C-NO2 partition was favorable at high temperature. The simulation results are helpful to deepen the insight into the thermal properties of condensed TATB.

Influence of Al and Al2O3 Nanoparticles on the Thermal Decay of 1,3,5-Trinitro-1,3,5-triazinane (RDX): Reactive Molecular Dynamics Simulations

“…However, this setup that is very common among ReaxFF-MD simulations has been confirmed to be feasible to reflect reaction mechansim. [46][47][48][49] Besides, for convenience, we define R as the ratio of the number of a chemical species to that of RDX to analyze reaction mechanism. Notably, 1500 K is the closest to the temperature adopted in the experiment, below 1000 K. 14,17,23,50 Therefore, the present result agrees with that the high activity of nano Al has frequently been shown to catalyze the thermal decomposition of RDX.…”

Anatomies for the thermal decomposition behavior and product rule of 5,5′-dinitro-2H,2H′-3,3′-bi-1,2,4-triazole

“…5 have been marked. There have references guiding and believing that the nucleation centers of nitro compounds and high-energy ionic salts come from the dissociation mechanism N-N and N]O (from-NO 2 ) and the p-p stacking between molecules, [49][50][51] where nitrogen atoms dissociate), while the ESP value of the le saddle point structure in the range of 0.75 Å to 1.5 Å (the C-N binding position), which is 0.52 eV higher than the initial structure. In Fig.…”

Reactive Molecular Dynamics Study on the Effect of H2O on the Thermal Decomposition of Ammonium Dinitramide

“…In order to obtain the initial reaction path of thermal decomposition of the reactants, according to the analysis method of Wen et al. , the chemical bond connection between atoms at different times was analyzed. Select the molecule whose atomic connection changes at the adjacent moments, then get the elementary reaction equation, and count the times of this type of elementary reaction within this time interval (that is, the frequency of this reaction).…”

“…By tracking the connection of small molecules (or fragments) at different times, and counting the small molecules (or fragments) whose connection changes in a very short time, the formation and breakage of different types of chemical bonds are obtained. In order to obtain the initial reaction path of thermal decomposition of the reactants, according to the analysis method of Wen et al [38], the chemical bond connection between atoms at different times was analyzed. Select the molecule whose atomic connection changes at the adjacent moments, then get the elementary reaction equation, and count the times of this type of elementary reaction within this time interval (that is, the frequency of this reaction).…”