The experimental detection and synthesis of pentazole (HN ) and its anion (cyclo-N ) have been actively pursued for the past hundred years. The synthesis of an aesthetic three-dimensional metal-pentazolate framework (denoted as MPF-1) is presented. It consists of sodium ions and cyclo-N anions in which the isolated cyclo-N anions are preternaturally stabilized in this inorganic open framework featuring two types of nanocages (Na N and Na N ) through strong metal coordination bonds. The compound MPF-1 is indefinitely stable at room temperature and exhibits high thermal stability relative to the reported cyclo-N salts. This finding offers a new approach to create metal-pentazolate frameworks (MPFs) and enables the future exploration of interesting pentazole chemistry and also related functional materials.

Continuous band structure tuning, e.g., doping with different atoms, is one of the most important features of inorganic semiconductors. However, this can hardly be realized in organic semicondutors. Here, we report the first example of fine-tuning organic semiconductor band structures by alloying structurally similar derivatives into one single phase. By incorporating halogen atoms on different positions of the backbone, BDOPV derivatives with complementary intramolecular or intermolecular charge distributions were obtained. To maximize the Coloumbic attractive interactions and minimize repulsive interactions, they form antiparallel cofacial stacking in monocomponent or in alloy single crystals, resulting in efficient π orbital overlap. Benefiting from self-assembly induced solid state “olefin metathesis” reaction, it was observed, for the first time, that three BDOPV derivatives cocrystallized in one single crystal. Molecules with different energy levels serve like the dopants in inorganic semiconductors. Consequently, as the total number of halogen atoms increased, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels of the alloy single crystals decreased monotonously in the range from −5.94 to −6.96 eV and −4.19 to −4.48 eV, respectively.

Powerful oxidizer N2O was incorporated into an organic lattice cavity through aeration crystallization, and smart host–guest energetic materials with highly-energetic and low-sensitivity performance were obtained.

Two new polymorphs of zeolite beta, denoted as SU-78A and SU-78B, were synthesized by employing dicyclohexylammonium hydroxides as organic structuredirecting agents. The structure was solved by combining transmission electron microscopy and single-crystal X-ray diffraction. SU-78 is an intergrowth of SU-78A and SU-78B and contains interconnected 12-ring channels in three directions. The two polymorphs are built from the same building layer, similar to that for the zeolite beta family. The layer stacking in SU-78, however, is different from those in zeolite beta polymorph A, B, and C, showing new zeolite framework topologies. SU-78 is thermally stable up to 600 °C.

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Three new energetic 2,2′,4,4′,6,6′-hexanitrostilbene (HNS) cocrystals, HNS/4,4′-bipyridine, HNS/trans-1,2bis(4-pyridyl)ethylene, and HNS/1,2-bis(4-pyridyl)ethane have been synthesized. A good geometric match and rich Hbonds have been observed between the selected coformer and HNS molecules in all three cocrystals. According to similar configuration and arrangement of HNS−coformer H-bonds, coformer−coformer π-stacking, and HNS−HNS H-bonding interactions, the three cocrystals have a common cocrystal architecture and show high thermal stability and improved sensitivity. This study is helpful for understanding the formation mechanism of energetic cocrystals and the design of new energetic cocrystals.

Solvent and heat induced self-assembly to CL-20/HMX co-crystals has been investigated. The mechanism towards such process could be concluded to nanoparticle inducing, oriented aggregation, surface integration and co-crystals assembly.

We report the crystal packing, electronic structure, Hirshfeld surface, Bader's atoms in molecules (AIM), and independent gradient model (IGM) for 2,2′,4,4′,6,6′-hexanitrostilbene (HNS) and HNS-based cocrystals (HNS/4,4′bipyridine (BP), HNS/trans-1,2-bis(4-pyridyl)ethylene (BPE), and HNS/1,2-bis(4-pyridyl)ethane (BPA)) to understand how noncovalent interactions affect the impact sensitivity of the cocrystals. The results indicate that there are strong C−H•••N interactions and π stacking in the three cocrystals. Among the three cocrystals, HNS/BP has the strongest intralayer hydrogen bonds and π−π interactions, which can be responsible for its lowest impact sensitivity. Among the emerging π−π interactions, the face to face interaction lying between components is the most important. Therefore, the strong intralayer hydrogen bonds and face to face π−π interactions determine the cocrystal explosives to have low impact sensitivity. Our work may provide useful information for understanding the safe performance of cocrystal explosives in atomic detail and broaden the application of supramolecular chemistry in the field of explosives.