3,4-Bis(3-tetrazolylfuroxan-4-yl)furoxan: A Linear C–C Bonded Pentaheterocyclic Energetic Material with High Heat of Formation and Superior Performance

Abstract

The design and preparation of new nitrogen-rich heterocyclic compounds are of considerable significance for the development of high-performing energetic materials. By combining nitrogen-rich tetrazole and oxygen-rich furoxan, a linear C–C bonded pentaheterocyclic energetic compound, 3,4-bis­(3-tetrazolylfuroxan-4-yl) furoxan (BTTFO), was synthesized using a facile and straightforward method. Comprehensive X-ray analysis reveals the key role of hydrogen bonds, π–π interactions, and short contacts in the formation of dense packing of BTTFO and explains why a long chain-shaped molecule has a high density. This multicyclic structure incorporating three furoxan and two tetrazole moieties results in an exceptionally high heat of formation (1290.8 kJ mol–1) and favorable calculated detonation performances (v D, 8621 m s–1, P, 31.5 GPa). The interesting structure and fascinating properties demonstrated the feasibility of a linear multicyclic approach as a high-energy-density skeleton. Additionally, the thermodynamic parameters, electrostatic potential (ESP), and frontier molecular orbitals were also studied to get a better understanding of structure–property correlations.

Strongly Confined and Spectrally Tunable CsPbBr3 Quantum Dots for Deep Blue QD‐LEDs

“…At higher Pb‐to‐Cs ratios, the PL peaks shifted more slowly at the elevated temperatures, indicating that the excess PbBr 2 slowed down the growth rate of QDs, as described in a previous study. [ 18b ] When a fixed Pb‐to‐Cs ratio of 1:1 and a larger number of ligands (1.5×) were used, the QDs exhibited violet‐blue emission at all the test temperatures ranging from 20 to 65 °C (Figure 3e), which is akin to the emission observed for a Pb‐to‐Cs ratio of 2:1 (Figure 3f). For a relatively lower ligand concentration, the QDs did not exhibit violet‐blue emission and instead showed a rapid spectral shift from deep blue (455 nm) to green (509 nm).…”

“…The FWHMs of the deep blue QDs were ≈20 nm, which were slightly larger than those of the violet‐blue region (Figure 1c), possibly due to a decrease in the Pb‐to‐Cs ratio at elevated temperatures. [ 18 ] At a temperature of 80 °C, the QDs exhibited a green emission at 501 nm and a broader FWHM of 27 nm. All the blue‐emitting samples demonstrate a small Stokes shift between the PL and the absorption peaks, indicating that most exciton recombination events occur around the bandgap without additional trap states.…”

“…The summary of EQE based on the CsPbBr 3 QDs and NPLs is shown in Figure 5e and Table S4 (Supporting Information). [ 10,16b,18b,19g,35 ] Moreover, the Commission Internationale de L'Eclairage (CIE) coordinates (0.14,0.03) and (0.15, 0.02), which are better than the blue Rec. 2020 standard of (0.13,0.04), shows that the emission device is suitable for deep blue display technology (Figure 5f).…”

Synthetic Strategies Toward Nitrogen-Rich Energetic Compounds Via the Reaction Characteristics of Cyanofurazan/Furoxan

“…From 3,4-dicyanofurazan 3 , some tetrazolylfurazans could be obtained from nitrile precursors ( Godovikova et al, 2009 ). After the convention of one cyano group to the fluorodinitromethyl group through cyanoaddition, diazotization, nitration, reduction, and fluorination, the other cyano group was then turned into a tetrazolyl moiety, leading to 3-(1H-tetrazol-5-yl)-4-fluorodinitromethylfuroxan 60 with excellent detonation properties (D: 8,923 m s −1 , P: 36.3 GPa) and broad application prospects in solid rocket propellants and explosives ( Zhai et al, 2020a ).…”

Computational investigation and screening of high‐energy‐density materials: Based on nitrogen‐rich 1,2,4,5‐tetrazine energetic derivatives

“…The molecular structure of this kind of nitrogen-rich compound contains a large number of N N, C N, N N, C N bonds, so that the heats of formation of the compound is mostly positive value, which is also beneficial to improve the molecular explosion heat. [24][25][26] In this paper, 1,2,4,5-tetrazine oxide rings with high energy were selected as the basic skeleton, and thirty six 1,2,4,5-tetrazine derivatives were designed with different Bridges ( CH 2 , NH , NH NH ) to connect tetrazole ring and furazan ring (Figure 2). The theoretical calculation of these compounds was carried out at the level of DFT-B3lYP/6-311+G*, the density of the compound is predicted, and the heats of formation is obtained using the atomic equivalent scheme.…”