Structural Transformations and Absorption Properties of Crystalline 7-Amino-6-nitrobenzodifuroxan under High Pressures

Abstract

The structural, electronic, and absorption properties of crystalline 7-amino-6-nitrobenzodifuroxan (ANBDF) under hydrostatic compression of 0–110 GPa have been studied by using DFT calculations. Our results show that there three structural transformations occurred at the pressure of 35, 70, and 100 GPa. The first structural transformation makes the positions of the molecules in the crystal rearranged and obviously improves the planarity. The second one forms a new C7–O10 covalent bond and transforms a boat conformation. The last one takes place with the rupture of the C7–O10 bond, forming another new C8–O10 covalent bond and transforming of a boat conformation to a chair. An analysis of the band gap and density of states of ANBDF indicates that its electronic character transforms into a metallic system at 70 GPa, and it becomes more sensitive under compression. The absorption spectra show that ANBDF has relatively high optical activity with the increasing pressure, and the structural transformations that occurred at 70 and 100 GPa can broaden its absorption region in the energy range of below 2 eV and above 20 eV, respectively. This work may provide useful information in understanding how ANBDF behaves under high pressures.

Electrochemical Properties of Al–based Solid Solutions Alloyed by Element Mg, Ga, Zn and Mn under the Guide of First Principles

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Dispersion-corrected DFT study on the structure and absorption properties of crystalline 5-nitro-2,4-dihydro-1,2,4-triazole-3-one under compression

“…Previous studies[20][21][22][23][24][33][34][35] have reported that the external pressure can induce the changes of molecular Struct Chem…”

Thermal decomposition mechanisms of the energetic benzotrifuroxan:1,3,3‐trinitroazetidine cocrystal using ab initio molecular dynamics simulations

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