Polymorphism in a Nonsensitive-High-Energy Material: Discovery of a New Polymorph and Crystal Structure of 4,4′,5,5′-Tetranitro-1H,1′H-[2,2′-biimidazole]-1,1′-diamine

Abstract

Polymorphism has attracted significant attention in the area of pharmaceutical chemistry and materials chemistry. For energetic materials, polymorphism may affect their physical performances such as energy, sensitivity, thermal stability, etc. 4,4′,5,5′-Tetranitro-1H,1′H-[2,2′-biimidazole]-1,1′-diamine (DATNBI) exhibits high density (d: 1.93 g cm–3), superior detonation performance (D: 9063 m s–1) and comprehensive sensitivity (IS: 15 J), suggesting it is a nonsensitive-high-energy material (NSHEM) compared with HMX as a sensitive-high-energy material (SHEM). In this work, a new polymorph of DATNBI was discovered for the first time. To elucidate its phase transformation behavior and morphology-performance relationship, single X-ray diffraction (SXRD), variable temperature powder X-ray diffraction (VT-PXRD), Raman spectroscopy, differential scanning calorimetry-thermal gravity (DSC-TG), and scanning electron microscopy (SEM) were characterized thoroughly. Solvation and temperature effects on the polymorph formation of DATNBI were also investigated.

Uncovering the Morphological Regulation Mechanism of Low Sensitivity and Highly Energetic Materials in Solvents: Changing Crystal Morphology Induced by Hydrogen Bonding

“…36 The results of our HS analysis are consistent with the results in previous reports, such as a platelike shape and the same interaction ratio (Figure 3), but we made a deeper analysis than that in the literature. 30 The HS of β-DATNBI is depicted in Figure 3, and two characteristics were found. First, its HS shows a platelike shape which means that the molecule is a planar conjugated structure.…”

“…Moreover, β-DATNBI owns two molecular configurations with a slight difference, but the variance between the molecular interactions is tiny. 30 Hence, one of the configurations was chosen to be analyzed in the study.…”

Molecular Forcefield Methods for Describing Energetic Molecular Crystals: A Review

“…For example, the Young’s modulus, bulk modulus, shear modulus, and Poisson’s ratio of RDX, HMX, and CL-20 crystals have been obtained using COMPASS FF based MD simulations under NPT ensemble [ 92 , 93 , 94 , 95 ]. The Young’s modulus and Possion’s ratio of newly synthesized energetic crystals α-DATNBI and β-DATNBI were also calculated using MD simulations and mechanical computations, with results showing that the mechanical properties of β-DATNBI are closer to β-HMX and better than α-DATNBI [ 96 ]. It should be noticed that mechanical calculations using COMPASS-MD have been applied for some of the nitro compounds or nitroamine explosives only, while rarely being applied for other EMs.…”

Polymorphism and solid state peculiarities in imidazo[1,5-a]pyridine core deriving compounds: An analysis of energetic and structural driving forces

“…inorganic-organic halide hybrid perovskites) 3 and high energy materials (propellants, explosives and pyrotechnics). [4][5][6] Polymorphism is the possibility of a molecule or of materials to crystallize with different crystal structures (having the same nature when melted) and, consequently, to show differences of their solid-state properties, influenced by symmetry and interactions. [7][8][9][10][11][12][13] However, also in the case of applications that involve the dissolved molecule, this aspect must be considered, especially in the case of different solubilities or bio-availabilities for each crystal form or the formation of different clusters in solutions that can influence properties like luminescence.…”

“…[40][41][42][43][44] We decided to focalize our attention on neutral or cationic organic crystal structures, leaving the study of metal complexes to another paper. Thus, we selected five systems (Scheme 1), with both a single and a double imidazo[1,5-a]pyridine nucleus: 1-(pyridin-2-yl)-3-(4-(trifluoromethyl)phenyl)imidazo[1,5-a]pyridine (1), 3-(4-(tert-butyl)phenyl)-1-(pyridin-2-yl)imidazo[1,5-a]pyridine (2), 1,4-bis(1-(pyridin-2yl)imidazo[1,5-a]pyridin-3-yl)benzene (3), 1,2-bis(1-(pyridin-2-yl)imidazo[1,5-a]pyridin-3-yl)ethane (4). These compounds have been crystallized in different solvents and several crystal forms have been detected and structurally characterized.…”