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Sultan, M.;  Wu, J.;  Haq, I.U.;  Imran, M.;  Yang, L.;  Wu, J.;  Lu, J.;  Chen, L. New Energetic Cocrystals. Encyclopedia. Available online: https://encyclopedia.pub/entry/26058 (accessed on 26 December 2025).
Sultan M,  Wu J,  Haq IU,  Imran M,  Yang L,  Wu J, et al. New Energetic Cocrystals. Encyclopedia. Available at: https://encyclopedia.pub/entry/26058. Accessed December 26, 2025.
Sultan, Manzoor, Junying Wu, Ihtisham Ul Haq, Muhammad Imran, Lijun Yang, Jiaojiao Wu, Jianying Lu, Lang Chen. "New Energetic Cocrystals" Encyclopedia, https://encyclopedia.pub/entry/26058 (accessed December 26, 2025).
Sultan, M.,  Wu, J.,  Haq, I.U.,  Imran, M.,  Yang, L.,  Wu, J.,  Lu, J., & Chen, L. (2022, August 10). New Energetic Cocrystals. In Encyclopedia. https://encyclopedia.pub/entry/26058
Sultan, Manzoor, et al. "New Energetic Cocrystals." Encyclopedia. Web. 10 August, 2022.
New Energetic Cocrystals
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This entry is adapted from the peer-reviewed paper 10.3390/molecules27154775

Cocrystallization refers to the orderly modification of the molecular structure of two or more elemental crystals without deteriorating the original bonding structure of the constituent crystals. The orderly arrangement of heterogeneous molecules having a fixed stoichiometry is the quintessence of cocrystallization. The resultant product thus formed is termed a ‘cocrystal’ and if one of the constituent crystals is an energetic material, the consequent cocrystalized product is called an ‘energetic cocrystal’ (ECC). ECCs are synthesized in an attempt to bridge the energy–safety contradiction of energetic materials (EMs),, and have this as one of their core objectives. For synthesis of an ECC, it is not necessary to synthesize a new energetic material; an existing EM can also be cocrystalized to form an ECC for appropriate applications. Cocrystallization, therefore, is a useful method for tuning the properties of Ems and producing designer, target-oriented EMs.

energetic materials detonation performance characterizations of ECCs

1. Synthesis Techniques

Cocrystal preparation processes include solid-state grinding, solution-reaction crystallization, solvent evaporation, and slurry conversion, and have all been extensively reported to date. Numerous synthesis techniques have been utilized for the creation of pharmaceutical cocrystals [1][2][3][4][5][6][7][8]. In addition, pharmaceutical cocrystals are easier to produce than energetic cocrystals (ECCs). Therefore, several ECC synthesis methods have been adapted from pharmaceutical cocrystal synthesis methods. The choice of an appropriate cocrystallization technique must still be made empirically. The two types of cocrystal-formation techniques that are most frequently employed are known as solution-based methods and solid-based methods. High solvent consumption is necessary in solution-based procedures in order to dissolve the cocrystal components. Additionally, the choice of solvent has an impact on the cocrystallization outcomes, since it might alter the interactions between EMs and the coformer molecules.

1.1. Solvent Evaporation

The basic principle of the solvent-evaporation technique for the synthesis of ECCs is that the constituent entities taking part in cocrystallization must have solubilities close to each other. If the participating materials have substantially different solubilities, the component with a lower solubility is likely to precipitate much faster than the other component, thereby leading to the formation of a mixture of solid cocrystal and other components [9]. In some cases, this can result in a complete collapse of the cocrystallization phenomenon. Therefore, care must be taken while choosing the cocrystallizing components to produce ECCs via the solvent-evaporation technique. In this method, the component cocrystals or coformers are dissolved in a solvent as per a pre-defined stoichiometric ratio with subsequent evaporation of the solvent in a sluggish manner to receive the final energetic cocrystals [10]. This method for ECC production is efficacious and cost-effective; however, these advantages are achieved at the cost of a few disadvantages. For instance, (i) this is not an environmentally friendly technique, because if the solvents used are toxic, they may impart hazardous vapors into the atmosphere if a proper disposal system is not installed; (ii) it takes a longer time to process, because the synthesis has to be accomplished at a lower rate of solvent evaporation; (iii) it is accompanied with augmented energy consumption because the evaporation is carried out at an escalated temperature; and (iv) it is difficult, at times, to accomplish the evaporation step in a controlled manner [11]. One of the examples of ECCs formed by the solvent-evaporation technique is the cocrystallization of HMX/AP, which is accomplished by the slow evaporation of the mixture. The hygroscopicity of AP and oxygen balance of HMX are simultaneously improved as a result of using this procedure.
The solvent-evaporation method is sometimes integrated with vacuum freeze-drying or spray-drying facilities to enhance the safety and quality factors. In vacuum freeze-drying, the solvent is removed from the solution of cocrystallizing components by freezing the solution with subsequent sublimation via the application of vacuum. The remaining solid is the cocrystallized energetic material. This method is used generally for heat-sensitive materials. Vacuum freeze-drying is relatively simple and safe because the volatility of hazardous vapors is much lower and the concentration of solvent is not observed during the course of the crystals’ precipitation [12]. However, this is an expensive technique due to the intensive energy consumption of the freezing process and its longer processing time. The product cost, therefore, increases manyfold, restricting its scaling and commercialization.
Another method to achieve ECCs is by solvent evaporation in a spray dryer, generally equipped with a two-fluid pneumatic nozzle, that introduces the suspension in the form of a very fine spray that comes across a co-current or countercurrent of hot air for the rapid removal of the solvent with the subsequent receipt of the final product from the bottom of a spray dryer [13]. The processing time here is much shorter than vacuum freeze-drying and other methods. The product achieved is a very fine powder with a narrower size distribution. The procedure is simple because the additional steps of product purification and solid–liquid separation are not required. However, spray drying is not environmentally friendly or safe because of the generation of some static electricity during the spray-drying process. The encapsulation of HMX by rather insensitive TATB (2,4,6-triamino-1,3,5-trinitrobenzene) particles is one such example of the coating of energetic materials via solvent evaporation in a spray dryer [14].

1.2. Solvent/Nonsolvent

Solvent/non-solvent is a frequently used method for the production of ECCs due to its convenience, simplicity, and safety. In this method, the precursor solution is prepared by the agitation of the cocrystallizing components in a solvent. This is followed by the introduction of a nonsolvent that gets the job done either by crystallization or coating of particles to precipitate the cocrystals. Despite its simplicity and convenience, the large quantity of the solvent used poses serious concerns with respect to the quality control of the finished product [13].

1.3. Cooling Crystallization

This is a quite simple and environmentally friendly method of cocrystallization. In this method, the crystallizing components, which must have a higher solubility, are dissolved in a solvent and the solution is cooled to an extent to achieve the state of oversaturation [15]. From this point onwards, the solute components cocrystallize and undergo a growth mechanism. In this method, at times, the solvent is one of the cocrystallizing components; for example, the cocrystal of pyridine and quinol is formed when quinol is dissolved in a predetermined volume of pyridine and cooled to form the desired cocrystal [16].

1.4. Grinding Methods

In this method, the energetic cocrystals are synthesized by mixing the components in a proportionate manner followed by processing in a ball mill or a mortar to receive the final cocrystallized product. No solvent is involved in the dry-grinding method; however, wet grinding involves the addition of a minimal quantity of solvent for cocrystallization. The dry-grinding method is suitable only for the production of small quantities of ECCs. The addition of a solvent in wet grinding facilitates the enhancement of the reaction rate, crystallinity, and efficiency of the production of the final cocrystals. Moreover, a solvent-assisted grinding method is better for energetic cocrystal formation, as it reduces the friction and heating during the synthesis of the cocrystals, which can be dangerous due to the sensitivity impact of energetic materials. Solvent-assisted grinding is an environmentally friendly method; however, it is difficult to control the cocrystals’ morphologies [13]. L. Yan et al. reported an energetic cocrystal (HNIW/TNT) synthesis using a solvent-assisted grinding method [17]. In their work, they used ethanol as a solvent due to its environmentally friendly nature.

1.5. Melting/Condensation Crystallization

The constituent components of cocrystallization are mixed as per the stoichiometric ratio and cooled below their melting temperature to form the cocrystals. Occasionally, the components evaporate and condense back to get the ECCs. This method is suitable for explosives with a broad difference in their melting and decomposition temperatures, such as TNT. It is not suitable for components that have higher melting and lower decomposition temperatures because such materials can undergo thermal decomposition. This method is highly efficient and, therefore, can be used for the industrial production of cocrystals. It is environment friendly because organic solvents are not utilized in this method [13].

1.6. Resonant Acoustic Method

This technology harnesses resonance to establish a highly efficient mixing operation for the cocrystallizing components. Since no baffles, impellers, propellers, or other moving parts are involved, this technology provides contactless mixing at the cost of lower energy consumption. In addition to meeting the functional requirements of the ECCs, this technique also caters for the safety requirements since it is highly unlikely to encounter a dangerous stimulation when cocrystallization is accomplished using a resonant acoustic method. With a stoichiometric ratio of 2:1, the production of CL-20/HMX energetic cocrystals is a typical example of this technique. This method has the added advantages of augmenting the mixing efficiency and enhancing the uniformity of the finished product [18].

1.7. Slurry Method

This method is comparatively simple in its operation. The constituent components, in a predetermined proportion, are gently stirred in a minute quantity of the solvent that acts as a mediator for the cocrystallization to take place. The slurry is continuously stirred until the reaction is completed and the ECC is formed. In this method, the solvent selection is critical, whereas the solubility factor is not critical [19].

1.8. Solvent-Suspension Method

CL-20/HMX cocrystallization with a stoichiometric ratio of 2:1 has been employed to produce ECCs successfully by using the solvent-suspension method, which is simple, safe, environmentally friendly, and produces cocrystals of higher crystallinity and a narrower particle-size distribution. In this method, a solvent (nothing other than deionized water) is used for cocrystallization. The components are added in deionized water and stirred for a long time (generally several hours) at a specific temperature with the subsequent filtration of the desired ECCs. This method is viable for the scaled-up production of ECCs [20].

1.9. Self-Assembly Method

This is an innovative method recently introduced for solvent-induced self-assembly of (i) a single energetic crystal with a non-energetic coformer, and (ii) both energetic components for the synthesis of ECCs. This technique involves (i) crystal particles’ induction, (ii) the aggregation of particles in an organized orientation, (iii) the integration of particles’ surfaces, and (iv) the formation of the ECC. Since the impact of heat and mass transfer operations is only minor in this method, it has an inherent convenience in the scaled-up production of ECCs.

2. Characteristics of ECCs

In this section, the focuses are on most significant characteristics of ECCs, including structural properties, detonation performance, sensitivity analysis, thermal properties, morphology mapping, and other properties such as oxygen balance, solubility, and fluorescence. The investigation of these characteristics paves the way for the efficacy analysis of the existing ECCs and design of new ECCs. In almost all of the studies reported in 2020–2021, the structural properties are investigated by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Raman spectroscopy, or Hirshfeld surface analysis. The detonation performance of ECCs is analyzed by the determination of detonation velocity, detonation pressure, or density concentration of the energetic molecules. One of the most important characteristics of ECCs is the sensitivity analysis of ECCs against external stimuli, be they impact sensitivity, friction sensitivity, spark sensitivity, or electric-field sensitivity. The sensitivity analysis is accomplished by the Bruceton method, BAM fall hammer method, and others. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) are mostly employed for the analysis of thermal stability and decomposition temperatures, while scanning electron microscopy (SEM) is generally used for the morphological study of the ECCs. All these characteristics, in addition to solubility, oxygen balance, and fluorescence, are discussed here.

2.1. Structural Properties of ECCs

The structural properties of ECCs display the philosophical underpinning of the molecular or atomic orientation of the cocrystals, which helps to determine the sensitivity and density concentration, thereby facilitating the design of new ECCs. There are different kinds of interactions that take place between the cocrystals, such as CH···O hydrogen-bonding interactions, CH···N hydrogen-bonding interactions, and NO2−π interactions. CL-20 is a well-known energetic material that is cocrystallized with several other coformers or energetic materials to synthesize ECCs or energetic–energetic cocrystals (EECCs). For example, ɛ-CL-20 is cocrystallized with TNT and the structural properties of the resultant ɛ-CL-20/TNT cocrystal are investigated using Hirshfeld surface analysis and reduced density gradient (RDG) analysis [21][22]. The benzene ring of TNT becomes an electron deficient π-system due to the strong polarizing effect of the nitro groups. A nitro group of CL-20, therefore, locates itself just above the center of the TNT benzene ring that holds the crystal structure intact via p-π stacking. The ɛ-CL-20/TNT ECC formation is driven by the O-H and N-O interactions while the ECC is stabilized by the O-O interactions. The Raman spectra, densities, and simulated lattice parameters are in synchrony with the experimental values [23][24].
The structural analysis of nano-CL-20/TNT (synthesized in a mechanical ball mill) reveals that ball milling does not alter the molecular orientation of the constituent materials. The resulting nano-CL-20/TNT features a novel crystal phase that differs from the crystal phase obtained by simple mixing [25]. The Hirshfeld surface analysis of 1:2 CL-20/benzaldehyde ECC indicates that overwhelmingly weak hydrogen bonding is the major driving force for the formation of CL-20/benzaldehyde ECC and stabilization of the crystal structure. The main molecular interactions in the crystal lattice include the O—H, O—N, and O—O interactions forming 60.2%, 15.3%, and 17.3%, respectively, of the surface area in the cocrystal. The cocrystal structure also witnesses additional O—C interactions between constituent components of the ECC [26]. Single crystal XRD and powder XRD of two energetic–energetic cocrystals (EECCs) with 1:1 and 1:3 CL-20/1-methyl-4,5-dinitroimidazole (4,5-MDNI) show strong intermolecular affinity between CL-20 and 4,5-MDNI in the form of hydrogen and NO2-π bonding that stabilizes the cocrystal structure. Different stacking orientations of the CL-20 and 4,5-MDNI also facilitate the stability of both the EECCs [27]. The crystal structure of ECCs can also be investigated using an evolutionary algorithm (USPEX) coupled with forcefields or ab initio calculations [28]. Similarly, the Hirshfeld surface analysis of CL-20/benzaldehyde ECC reveals the formation of cocrystals by strong hydrogen bonding with a triclinic system [26][29].
Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), the most powerful military explosive, has been cocrystallized in several new studies to make ECCs. For example, HMX has been cocrystallized with N,N-Bis(trinitroethyl)nitramine (BTNEN) to form HMX/BTNEN ECC. The cocrystallization of HMX and BTNEN changes the electron density due to the hydrogen bonding of the resulting ECC. The crystal structure of HMX/BTNEN is different than the structures of individual coformers such that the new positions of ECC diffraction angles are 7, 13, 14.2, 19.7, and 33.2 degrees [30]. Density functional theory (DFT) is employed to study the crystal structure of HMX/FOX-7 (1,1-diamino-2,2-dinitroethylene) ECC. The hydrogen bonding strengthens the N-NO2 bonding while increasing the bond-dissociation energy of N-NO2 [31]. Another HMX-based ECC was prepared by the solvent/non-solvent method with an insensitive explosive, 6-diamino-3,5-dinitropyridine-1-oxide (ANPyO). The XRD spectrum of the simple mechanical mixture of components appears to be merely a superposition of the individual components, whereas the XRD spectrum of the ECC of HMX/ANPyO is entirely different, thereby implying the formation of the cocrystal. A strong hydrogen bonding exists between the ―NH2 of ANPyO and ―NO2 of HMX in the HMX/ANPyO ECC. The HMX molecule is replaced by an ANPyO molecule into the crystal lattice [32].
Benzotrifuroxin (BTF) is cocrystallized with various coformers such as trinitrobenzene (TNB), TNT, trinitroaniline (TNA), trinitrobenzene methylamine (MATNB), and 1,3,3-trinitroazetidine (TNAZ). The powder XRD and single XRD analysis reveals that the ECC formation is mainly governed by strong hydrogen bonding [33] in addition to p—π and π—π stacking interactions. The six-membered ring of BTF consists of an electron-poor π-system, so it is natural that BTF would have higher chances of producing ECC with compounds that have a higher number of electron-rich groups [34]. Rapid cocrystallization by the use of differential solubility is employed to synthesize two ECCs, namely, TNB/2,4-MDNI and CL-20/1-methyl-3,4,5-trinitropyrazole (MTNP), and the analysis of intermolecular interactions reveals that both of these ECCs possess stronger intermolecular interactions that are governed by the nitro—π bonding [35]. 
Furthermore, 4,4,5,5-tetranitro-2,2-biimidazole (TNBI) is cocrystallized with fifteen coformers and the characteristics of four of them are thoroughly investigated. The structural analysis reveals that the cocrystal formation is driven by the hydrogen bonding of N—H…N and N—H…O between TNBI and the corresponding coformers. The crystallographic investigation further suggests that an optimum oxygen balance driven by N-oxide-based acceptors produces much better energetic materials. The shelf life and stability of these ECCs is also improved due to their imperviousness to humidity and, therefore, these ECCs can substitute for TNBI materials in industrial applications [36]. The absence of N—H protons in the resulting ECC lowers the hygroscopicity and chemical acidity of the parent compound thereby enhancing its handling, storage, and transport [37].
Maximizing the intermolecular interactions by any means, such as hydrogen bonding or π-stacking, can be utilized for the synergistic detonation performance of EMs. With this intention, a 1:2 ECC is produced from 4H, 8H-difurazano[3,4-b:3′,4′-e] pyrazine and hydroxyl-amine coformers. The resulting ECC displays characteristics akin to 1,3,5-triamino-2,4,6-trinitrobenzene especially the detonation properties are found to be much better than the mechanical mixture of the constituent components. In addition, the detonation performance of the ECC appears to be superior to theoretical prediction, providing it with synergistic properties. This is achieved by (i) appropriate pairing of the cocrystallizing molecules, (ii) developing setups that have H-donor and -acceptor sites, (iii) electron deficient and rich π-systems that ultimately result in an increase in the density of the consequent ECC through strong intermolecular interactions [38].
An ECC based on a 6:1 cyclopentazolate anion (NH4N5) and ammonium chloride is synthesized by employing the slow-solvent-evaporation method. The crystal structure indicates cube-shaped NH4N5/NH4Cl cocrystals that are formed by hydrogen bonding. The cocrystals are formed mainly by the N—H···N and N—H···Cl hydrogen bonds, and π-π interactions. Due to this crystal structure, the ECC is found to have a higher decomposition temperature, lower sensitivity, and improved detonation performance as compared to the individual coformers [39].

2.2. Detonation Performance of ECCs

The efficacy of an EM or ECC is determined by its detonation performance, which is measured in terms of various factors such as detonation velocity, detonation pressure, and crystal density. Various methods are reported in the literature for the evaluation of the detonation performance of ECCs. Rothstein and Petersen propose a simple, empirical proportion between detonation velocity (D) at theoretical maximum density and detonation factor (F) that is only based on chemical composition and structure for perfect C, H, N, O-type explosives [40][41]. The detonation factor F is given as
A comparable crystal density of CL-20 and TNT results in an augmented density of the CL-20/TNT cocrystal [23]. The detonation pressure and detonation velocity of a CL-20/benzaldehyde ECC is found to decrease as compared to the pristine CL-20. However, the impact sensitivity of this ECC is decreased. Therefore, such an ECC is suitable for applications where a lower impact sensitivity is required despite a poor detonation performance. The detonation velocity (7455 m/s) is lower than detonation velocity of CL-20 and TNT [26][42].
Another kind of ECC is the energetic–energetic cocrystal (EECC) in which one EM is cocrystallized with another EM to form an EECC. For example, CL-20/4,5-MDNI ECC is cocrystallized with different ratios (1:3 and 1:1) to study the thermal, morphological, and detonation characteristics of the resulting EECC. The results indicate superior detonation performance for 1:1 EECC as compared to 1:3 EECC. The 1:3 ECC is less sensitive, but its detonation performance (D: 8604 m/s, P: 34.45 GPa), however, is better than the recently introduced insensitive ECC LLM-105 (2,6-diamino-3,5-dinitropyrazine-l-oxide). The impact sensitivity of 1:3 EECC is close to that of LLM-105. The results suggest that the stoichiometric ratio of the EM can be manipulated to design new EECCs with improved characteristics. The 1:3 EECC can be regarded as a new high-energy ECC with low impact sensitivity [27].
FOX-7 is cocrystallized with b-HMX and the resulting ECC density (1.9 g/cm3) is found to be a little lower than HMX and higher than that of FOX-7 and the same goes for the detonation performance—that is, the detonation performance of b-HMX/FOX-7 ECC is lower than HMX but higher than FOX. Despite a lower detonation performance (detonation velocity = 9.162 km/s) as compared to HMX, this ECC can still be described as a high-density energetic material and an effective explosive. A comparison of the characteristics of two ECCs, that is, CL-20/MTNP and TNB/2,4-MDNI, indicates that CL-20/MTNP has lower impact sensitivity and an augmented density and detonation velocity as compared to the widely known benchmark HMX, which makes it viable for commercial production [35].

2.3. Sensitivity Analysis of ECCs

The sensitivity analysis of EMs is extremely important for the design of explosives. It is imperative to determine the factors and the extent to which they affect the sensitivity of ECCs [43]. An ideal ECC is the one that possesses the highest detonation performance or energy content and the lowest possible sensitivity. CL-20/TNT ECC exhibits lower sensitivity as determined by the radial distribution function (RDF) vibrational analysis. The lower sensitivity is attributed to the p-π stacking of the nitro groups of CL-20 and the benzene rings of TNT that keep the crystal structure intact. An overwhelming polarizing effect of TNT’s nitro groups constitute an electron-deficient π-system with consequent positioning of the ―NO2 group of CL-20 exactly above the center of TNT’s benzene ring [23]. Another study on nano-CL-20/TNT ECC reveals reduced friction and impact sensitivities as compared to pristine nano-CL-20 and TNT, thereby suggesting the improved safety and viability of this cocrystal explosive in comparison to CL-20 [25].
The Bruceton method is used to study the impact sensitivity of a 1:2 CL-20/benzaldehyde ECC and the findings imply a reduced impact sensitivity, likely for two reasons: (i) the strong hydrogen bonding produces a stable crystal structure that is immune to sudden shock; and (ii) the layered stacking of the crystal lattice also imparts stability to the CL-20/benzaldehyde cocrystal and, therefore, the friction or shock forces are dissipated by the well-packed layers of the cocrystal, thereby decreasing the impact sensitivity. However, this enhanced impact sensitivity is achieved at the cost of a lower detonation velocity and pressure. Thus, it is suggested that such an ECC can be used for applications where high explosive power is not desired [26].
Sometimes, a catastrophic explosion can take place when the ECCs encounter an external electric field. To avoid this, it is important to understand the impact of electric fields on sensitivity and other properties of ECCs in an external electric field so that preemptive abatement strategies can be designed to combat any unforeseen explosion. Several CL-20-based ECCs including CL-20/BTF, CL-20/DNP (3,4-dinitropyrazole), and CL-20/MDNT (1-methyl-3,5-dinitro-1,2,4-triazole) were subjected to an external electric field to investigate its effect on sensitivity and other characteristics of the ECCs. It was found that CL-20/BTF is the most sensitive ECC because of its augmented chemical reactivity, in addition to having the smallest energy gap due to a positive energy field as shown by the electron structure analysis. The analysis of the bond-dissociation energy (BDE) of N-NO2 and H50 reveals that an increase in a positive electric field renders the impact sensitivity, smaller BDE, and longer trigger-bond length even more sensitive. The increase in negative nitro group charge in a negative external electric field reduces the sensitivity of the ECCs. The larger the negative electric field, the higher the negative charge of the nitro groups, and the lower the sensitivity [44].
The impact sensitivity of ECCs is a function of the intermolecular interactions and packing density of the molecules. An ECC of 2:1 HMX/BTNEN was subjected to the standard GJB-772-97 method for the evaluation of the impact sensitivity of the energetic cocrystal by drop height resulting in a 50% explosion probability (H50). The H50 value of the 2:1 HMX/BTNEN ECC is found to be 55 cm—that is, in between the H50 values of HMX (63 cm) and BTNEN (50 cm), indicating that the synthesized ECC is less impact-sensitive than pure BTNEN. This decrease is attributed to the enhanced packing density of the ECC molecules due to strong intermolecular interactions. Designer ECCs can, therefore, be produced by manipulating the intermolecular interactions by various means [30]. Another study reports similar results in terms of enhanced hydrogen bonding, resulting in a diminished mechanical sensitivity in the case of a hydrazine 3-nitro-1,2,4-triazol-5-one (HNTO)/ammonium nitrate (AN) ECC [45][46].
BTF is cocrystallized with various coformers such as TNB, TNT, TNA, MATNB, and TNAZ, and the drop-weight impact data reveal that BTF/TNB and BTF/TNT ECCs have much lower sensitivities as compared to pristine BTF. In particular, the BTF/TNB ECC is more significant because it possesses explosive properties comparable with RDX but is less sensitive as compared, which vindicates its viability for explosive applications [34].

Abbreviations

AP Ammonium perchlorate
ANPYO 6-diamino-3,5-dinitropyridine-1-oxide
ATRZ 4,4′-azo-1,2,4-triazole
BTNEN N,N-Bis(trinitroethyl)nitramine
BTF Benzotrifuroxin (BTF)
CL-20 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane
DFT Density functional theory
DNP 3,4-dinitropyrazole
DSC Differential scanning calorimetry
EM Energetic material
ECC Energetic cocrystals
FOX-7 1,1-diamino-2,2-dinitroethylene
HMX 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane
HNTO Hydrazine 3-nitro-1,2,4-triazol-5-one
HNIW 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane
2,4-MDNI 1-methyl-dinitroimidazole
MATNB Trinitrobenzene methylamine
MDNT 1-methyl-3,5-dinitro-1,2,4-triazole
MTNP 1-methyl-3,4,5-trinitropyrazole
PLIF Planar laser-induced fluorescence
RDG Reduced density gradient
SEM Scanning electron microscopy
TNT Trinitrotoluene
TNB Trinitrobenzene
TNA Trinitroaniline
TNAZ 1,3,3-trinitroazetidine
TNBI 4,4,5,5-tetranitro-2,2-biimidazole
TITNB 1,3,5-triiodo-2,4,6-trinitrobenzene
TATB 2,4,6-triamino-1,3,5-trinitrobenzene
TFAZ 7H-trifurazano[3,4-b:3′,4′-f:3″,4″-d]azepine
TGA Thermogravimetric analysis
2,4-MDNI l-methyl-2,4-dinitroimidazole

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Subjects: Energy & Fuels
Contributors MDPI registered users' name will be linked to their SciProfiles pages. To register with us, please refer to https://encyclopedia.pub/register :
Manzoor Sultan
, Junying Wu , Ihtisham Ul Haq ,
Muhammad Imran
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Lijun Yang
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JiaoJiao Wu
,
Jianying Lu
,
Lang Chen
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Update Date: 11 Aug 2022
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