Bonding analysis of the effect of strain on trigger bonds in organic-cage energetic materials

Intra‐Ring Bridging: A Strategy for Molecular Design of Highly Energetic Nitramines

“…The results of the different bonds among the gained molecules are depicted in Table 1. As other studies reported, [ 31‐33 ] the trigger bonds of CL‐20 are the N—NO 2 bonds. Therefore, CL‐20 is chosen as the reference molecule to measure the trigger bonds, and only the minimum of WBI for each molecule is considered and compared.…”

Alleviating the stability–performance contradiction of cage-like high-energy-density materials by a backbone-collapse and branch-heterolysis competition mechanism

“…23 One possible reason is that the strain energy of the caged molecules increases the total energies of the HEDMs, without significantly weakening their chemical bonds. 24,25 Therefore, the detonation performance of the caged HEDMs can be improved without compromising much of their stability under extra stimuli. Recently, a novel cagelike HEDM was theoretically designed through a large-scale database search, and the designed ZN-OB 9 compound was quantified to show satisfactory stability and better performance than CL-20, suggesting the effectiveness of the strategy.…”

“…23 Reaction kinetics are critical for understanding the initiation and energy release of HEDMs under various conditions. 26,27 Over the past few decades, numerous atomistic calculations have been conducted to reveal the initial reaction kinetics of the synthesized compounds with cage-like backbones, such as CL-20, [28][29][30][31][32][33][34] heptanitrocubane (HNC), 25,35 octanitrocubane (ONC), 25,35 and 4,10dinitro-2,6,8,12-tetraoxa-4,10-diazaisowurtzitane (TEX), 36 when exposed to thermal or shock stimuli. [28][29][30][31][32][33] The heterolysis of the N-NO 2 bond and the fracture of the C-N/C bonds in the caged backbone were found to be the main paths to initialize the reaction of CL-20 crystals.…”

“…For HNC and ONC, the thermal reaction is initialized by the fracture of the C-C bonds in the caged backbone or the isomerization of the molecules. 25,35 In contrast, the heterolysis of the N-NO 2 bonds in the branches precedes the bond fracture in the backbone during the initiation of TEX thermolysis. 36 The competition mechanism between branch-heterolysis and backbone-collapse is critical for understanding the initiation and energy release of HEDMs under controlled conditions.…”

Some Novel Tricyclic Caged-Nitramines - A DFT Study

“…The effect of strain on trigger bonds in organic-cage energetic materials, including nitramines was reported [14]. Extension of the research, concentrated on caged nitramines such as TEX and CL-20 have attracted attention in recent years [15][16][17][18][19][20][21][22].…”