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The density functional theory method was employed to calculate three-dimensional structures for a series of novel explosophores. The design of new molecules (DA1–DA12) was based on the bridge-ring structures that could be formed via Diels–Alder (DA) reaction of selected nitrogen-rich dienes and tetranitroethylene dienophile. The feasibility of the proposed DA reactions was predicted on the basis of the molecular orbital theory. The strong interactions between the HOMO of dienes, with electron-donating groups (Diene2, Diene6, and Diene8), and the LUMO of tetranitroethylene dienophile suggested thermodynamically favorable formation of the desired DA reaction products. In addition to molecular structures of the explored DA compounds, their physicochemical and energetic properties were also calculated in detail. Due to compact bridge-ring structures, new energetic molecules have highly positive heats of formation (up to 1124.90 kJ·mol–1) and high densities (up to 2.04 g·cm–3). Also, as a result of all-right ratios of nitrogen and oxygen, most of the new compounds possess high detonation velocities (8.28–10.02 km·s–1) and high detonation pressures (30.87–47.83 GPa). Energetic compounds DA1, DA4, and DA12exhibit a superior detonation performance over widely used HMX explosive, and DA5, DA7, and DA10could be comparable to the state-of-the-art CL-20 and ONC explosives. Our proposed designs and synthetic methodology should provide a platform for the development of novel energetic materials with superior performance.

A vertical gate symmetrical molecular transistor is demonstrated. It includes self-assembled monolayer of ferrocene molecules chemically bonded to be a flat Au source and Au nanoparticles drain electrodes while gated with the central gate electrode. Using this configuration, we show that negative differential resistance, symmetrical behavior, and rectification effects can be tuned by controlling the gate voltage. The I–Vcurves shift from symmetric to strongly rectifying over a gate voltage range of a few tenths of volts around a threshold value where the junction behaves symmetrically. This is due to charging of the nanoparticle contact, which modifies the spatial profile of the voltage across the junction, a fact that we have included in a simple theoretical model that explains our experimental results quite well. Our device design affords a new way to fine-tune the rectification of molecular devices in a way that does not necessarily involve the Coulomb charging of the wire.