Development and Evolution of Energetic Cocrystals.

In spite of the importance of energetic materials to a broad range of military (munitions, missiles) and civilian (mining, space exploration) technologies, the introduction of new chemical entities in the field occurs at a very slow pace. This situation is understandable considering the stringent requirements for cost and safety that must be met for new chemical entities to be fielded. If existing manufacturing infrastructure could be leveraged, then this would offer a fundamental shift in the discovery paradigm.

Thermal decomposition pathways of nitro-functionalized metal-organic frameworks.

The decomposition behavior of high energy metal-organic frameworks (MOFs) with extensive nitration is disclosed. In contrast to the detonation behavior observed in molecular energetic compounds, deflagration transforms cubic MOFs into anisotropic carbon structures with highly dispersed metal. Both the structural metal and intimate mixing are found to be critical.

A melt castable energetic cocrystal.

An energetic cocrystal is described between 3,4-diaminofurazan (DAF) and 4-amino-3,5-dinitropyrazole (ADNP). The material is remarkable because interaction between the components leads to melting behavior and melt-state stabilization (absent in ADNP), that allows a melt castable formulation with explosive performance superior to DAF. This provides another potential advantage of cocrystallization for energetic materials.

Hydrogen Peroxide Solvates of 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane.

Two polymorphic hydrogen peroxide solvates of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20; wurtzitane is an alternative name to iceane) were obtained using hydrated α-CL-20 as a guide. These novel H O solvates have high crystallographic densities (1.96 and 2.

Rendering non-energetic microporous coordination polymers explosive.

Adsorption of oxidizing guest molecules into a non-energetic microporous coordination polymer produces explosives with desirable oxygen balance, high heat released upon decomposition, and suppressed vapor pressure of the guest. Here, this results in primary explosives, materials very sensitive to impact, that have the potential to be used as replacements for lead-based initiators.

Synthesis and photophysical properties of biphenyl and terphenyl arylene-ethynylene macrocycles.

A series of single-walled carbon nanotube precursors, C3h-symmetric cyclotri(ethynylene)(biphenyl-2,4'-diyl) and cyclotri(ethynylene)(p-terphenyl-2,4″-diyl), have been prepared by a linear stepwise oligomerization-cyclization route and by statistical intermolecular cyclooligomerization. In addition to producing these members of a novel class of arylene ethynylene macrocycles, 1 and 2, the latter statistical process produces the smaller cyclic dimer, cyclodi(ethynylene)(p-terphenyl-2,4″-diyl) and the larger cyclic tetramer cyclotetra(ethynylene)(biphenyl-2,4'-diyl). These macrocycles display large Stokes shifts in their fluorescence spectra.