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Title: Engineering bistetrazoles: ( E )-5,5′-(ethene-1,2-diyl)bis(1 H -tetrazol-1-ol) as a new planar high-energy-density material
Energetic properties of bistetrazole derivatives are improved by the step-by-step introduction of functionalities which improve heat of formation, density, and oxygen content. The incorporation of unsaturation between bis(1 H -tetrazol-5-yl) and bis(1 H -tetrazol-1-ol) derivatives leads to planarity which enhances the density of the final product. In this manuscript, we have synthesized compounds 1,2-di(1 H -tetrazol-5-yl)ethane (4), ( E )-1,2-di(1 H -tetrazol-5-yl)ethene (5), and ( E )-5,5′-(ethene-1,2-diyl)bis(1 H -tetrazol-1-ol), (6) using readily available starting materials. Their corresponding dihydroxylammonium salts 7, 8 and 9 are obtained by reacting two equivalents of hydroxylamine (50% in water). New compounds are analyzed using IR, EA, DSC and multinuclear NMR spectroscopy ( 1 H, 13 C and 15 N). The solid-state structures of compounds 6, 7, 8 and 9 are confirmed by single-crystal X-ray diffraction. The energetic performances are calculated using the EXPLO5 (v6.06.02) code and the sensitivities towards external stimuli such as friction and impact are determined according to BAM standard. Compound 6 {( E )-5,5′-(ethene-1,2-diyl)bis(1 H -tetrazol-1-ol)} exhibits a surprisingly high density of 1.91 g cm −3 at 100 K (1.86 g cm −3 at 298 K). Its detonation velocity (9017 m s −1 ) is considerably superior to those of RDX (8795 m s −1 ), which suggests it is a competitive high-energy-density material.  more » « less
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Date Published:
Journal Name:
Materials Advances
Page Range / eLocation ID:
6062 to 6068
Medium: X
Sponsoring Org:
National Science Foundation
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