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Nano-MnFe 2 O 4 particles were synthesized by co-precipitation phase inversion method and low-temperature combustion method respectively, using MnCl 2 , FeCl 3 , Mn(NO 3) 2 , Fe(NO 3) 3 , NaOH and C 6 H 8 O 7. X-ray diffraction (XRD), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry-differential thermal analysis (TG-DTA) and differential scanning calorimetry (DSC) were used to characterize the structure, morphology, thermal stability of MnFe 2 O 4 and its catalytic performance to ammonium perchlorate. Results showed that single-phased and uniform spinel MnFe 2 O 4 was obtained. The average particle size was about 30 and 20 nm. The infrared absorption peaks appeared at about 420 and 574 cm −1 , and the particles were stable below 524 °C. Using the two prepared catalysts, the higher thermal decomposition temperature of ammonium perchlorate was decreased by 77.3 and 84.9 °C respectively, while the apparent decomposition heat was increased by 482.5 and 574.3 J•g −1. The catalytic mechanism could be explained by the favorable electron transfer space provided by outer d orbit of transition metal ions and the high specific surface absorption effect of MnFe 2 O 4 particles. Keywords MnFe 2 O 4 , co-precipitation phase inversion method, low-temperature combustion method, ammonium perchlorate, catalysis

[reaction: see text]. The Kyodai nitration of toluene and chlorobenzene has been examined in the presence of a solid inorganic catalyst (montmorillonite K10, zeolite HZSM-5, or HBEA-25). Regioselection was quite low at the mononitration stage, but a considerably high preference for the 2,4-isomer was observed at the dinitration stage.

Previous studies have shown that the design of cocrystal explosives is one of the most promising approaches to decrease the sensitivity and maintain the detonation performance of existing explosives. As is well‐known, octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX) is a high energy density material (HEDM). But the application of HMX is limited, due to its high sensitivity. Thus, an insensitive explosive 5‐nitro‐1,2,4‐triazol‐3‐one (NTO) is proposed as a cocrystal former (CCF) to cocrystallize with HMX in the present work. The binding energies, heat of formations (HOFs), thermodynamic properties, atoms in molecules, and natural bond orbital analysis of four HMX/NTO complexes have been calculated using density functional theory methods, including meta‐hybrid functional (M062X) and dispersion‐corrected density functionals (B97D, ωB97XD). In addition, the crystal structure of HMX/NTO cocrystal has been investigated using Monte Carlo simulation and first principles methods. The HMX/NTO cocrystal is most likely to crystallize in triclinic crystal system with P1 space group, and corresponding cell parameters are Z = 2, a = 9.06 Å, b = 8.19 Å, c = 10.27 Å, α = 81.94°, β = 98.42°, γ = 82.03°, and ρ = 1.92 g/cm3. The detonation velocity and detonation pressure of HMX/NTO cocrystal are 8.73 km/s and 35.14 GPa, respectively, a little lower than those of HMX. Finally, bond dissociation energies (BDEs) of the weakest trigger bond in HMX/NTO complexes are calculated. The results show that HMX/NTO complexes are thermally stable and meet the thermal requirement of HEDMs (BDE > 120 kJ/mol). © 2012 Wiley Periodicals, Inc.

Intermolecular interactions and properties of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) / 2,6-diamino-3,5dinitropyrazine-1-oxide (LLM-105) cocrystal were studied by using the dispersion-corrected density functionals (ωB97XD, B97D) and meta-hybrid functional (M062x) methods. Binding energies, heats of formation, thermodynamic properties, atoms in molecules, and natural bond orbital analysis were performed to investigate HMX/LLM-105 complexes. Results show that the main intermolecular interactions between HMX and LLM-105 are CH…O, NH…O, N…O, and O…O interactions. In addition, Monte Carlo simulation was employed to predict the crystal structure of HMX/LLM-105 cocrystal. The HMX/LLM-105 cocrystal is most likely to crystallize in C2/c space group, and its corresponding cell parameters are Z = 8, a = 41.63 Å, b = 6.77 Å, c = 45.63 Å, ß = 164.55°, and ρ = 1.99 g/cm 3 . Detonation velocity and pressure of HMX/LLM-105 cocrystal are 8.95 km/s, 37.69GPa, a little lower than those of HMX (9.10 km/s, 37.76GPa). However, according to the net charges of nitro group, HMX/LLM-105 cocrystal exhibits less sensitive than HMX. Finally, bond dissociation energy calculation shows that HMX/LLM-105 complexes are thermally stable. Considering thermal stability, sensitivity, and detonation performance, HMX/LLM-105 cocrystal meets the requirements of insensitive high energy density materials.