Metal-organic frameworks (MOFs) have attracted great attention because of their intriguing molecular topologies and potential applications in chemical separation, [1] gas storage, [2] drug delivery, [3] catalysis [4] and chemical sensor technology. [5] Particularly, MOFs could also be potential energetic materials because of their high densities and high heats of detonation. For example, Hope-Weeks and co-workers recently reported two hydrazine-perchlorate 1D MOFs [(Ni(NH 2 NH 2 ) 5 (ClO 4 ) 2 ) n (NHP), and (Co(NH 2 NH 2 ) 5 (ClO 4 ) 2 ) n (CHP)] with linear polymeric structures, [6] which were regarded as possibly the most powerful metal-based energetic materials known to date, with heats of detonation comparable with that of hexanitrohexaazaisowutzitane (CL-20; about 1.5 kcal g À1 ).Unfortunately, these coordination polymers were highly sensitive to impact deriving from their low rigidity characteristic of such linear polymeric structures, which makes practical use infeasible. In order to decrease the sensitivities, the same authors also used a hydrazine derivative (hydrazine-carboxylate) as the ligand to construct MOFs with 2D sheet structures [((

We present an application of the reaction class transition state theory (RC-TST) in predicting thermal rate constants of the hydrogen abstraction reactions H + H-C(sp 3 ) where C(sp 3 ) is a saturated carbon atom. Combining the RC-TST with the linear energy relationship (LER) allows rate constants of any reaction in the class to be estimated from only reaction energy information. We have derived from first-principles all parameters for the RC-TST/LER method so rate constants for any reaction in this class can be predicted from only reaction energy, that can easily be computed from either the density functional theory or semiempirical molecular orbital theory. We have performed error analyses for a large number of reactions in the above class for which some experimental measurements or estimates are available. By comparisons with results from full TST/Eckart calculations we also found the RC-TST/LER method is quite cost-effective and has accuracy comparable to first-principles predictions using more rigorous methodologies.

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Accurate prediction to the detonation performances of different kinds of energetic materials has attracted significant attention in the area of high energy density materials (HEDMs). A common approach for the estimation of CHNO explosives is the Kamlet-Jacobs (K-J) equation. However, with the development of energetic materials, the components of explosives are no longer restricted to CHNO elements. In this study, we have extended the K-J equation to the calculation of certain metal-containing explosives. A new empirical method, in which metal elements are assumed to form metallic oxides, has been developed on the basis of the largest exothermic principle. In this method, metal oxides can be deemed as inert solids that release heat other than gases. To evaluate the prediction accuracy of new method, a commercial program EXPLO5 has been employed for the calculation. The difference involved in the ways of treating products has been taken into account, and the detonation parameters from two methods were subject to close comparison. The results suggest that the mean absolute values (MAVs) of relative deviation for detonation velocity (D) and detonation pressure (P) are less than 5%. Overall, this new method has exhibited excellent accuracy and simplicity, affording an efficient way to estimate the performance of explosives without relying on sophisticated computer programs. Therefore, it will be helpful in designing and synthesizing new metallic energetic compounds.

Energetic polynitro anions, such as dinitramide ion [N­(NO2)2 –], have attracted significant interest in the field of energetic materials due to their high densities and rich oxygen contents; however, most of them usually suffer from low stability. Conveniently stabilizing energetic polynitro anions to develop new high energy materials as well as tuning their energetic properties still represent significant challenges. To address these challenges, we herein propose a novel strategy that energetic polynitro anions are encapsulated within energetic cationic metal–organic frameworks (MOFs). We present N­(NO2)2 – encapsulated within a three-dimensional (3D) energetic cationic MOF through simple anion exchange. The resultant inclusion complex exhibits a remarkable thermal stability with the onset decomposition temperature of 221 °C, which is, to our knowledge, the highest value known for all dinitramide-based compounds. In addition, it possesses good energetic properties, which can be conveniently tuned by changing the mole ratio of the starting materials. The encapsulated anion can also be released in a controlled fashion without disrupting the framework. This work may shed new insights into the stabilization, storage, and release of labile energetic anions under ambient conditions, while providing a simple and convenient approach for the preparation of new energetic MOFs and the modulation of their energetic properties.