Based on the unique advantages of terahertz (THz) spectrum on the detection of energetic cocrystals, the low-temperature dependent THz spectra of CL-20/TNT cocrystal were investigated by using molecular dynamics (MD) simulations from 5 to 296 K, as well as three different crystal faces, (001), (120), and (010). When the temperature decreases below 95 K, we have observed two new peaks for CL-20/TNT cocrystal, at 4.58 and 5.99 THz, respectively. Also, the THz peaks below 1.5 THz gradually disappear under cooling from 296 to 5 K, and they should originate from the lattice thermal vibrations. THz absorption peaks of CL-20/TNT cocrystal reveal frequency shifting, linearly dependent on temperature. Four of them are red shift and other two are blue shift of THz vibrational peaks of CL-20/TNT cocrystal with the temperature increase. The frequency shifts can be attributed to the effects of lattice thermal expansion on inter-/intramolecular vibrational modes as well as their coupling. From the temperature-dependent THz spectra of different crystal faces, we further confirm the response of different kinds of intermolecular interactions on the THz spectrum of CL-20/TNT cocrystal. Graphical abstractThe intermolecular interactions and peak positions of THz spectra of CL-20/TNT cocrystal in the range of 0-6 THz versus temperature.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/s00894-019-4270-6 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Preparation and Molecular Dynamic Simulation of Superfine CL-20/TNT Cocrystal Based on the Opposite Spray Method.
Int J Mol Sci
August 2024
School of Environmental and Safety Engineering, North University of China, Taiyuan 030051, China.
Article Synopsis
- The study addresses issues in the slow crystallization rate and safety of preparing CL-20/TNT cocrystal explosives by introducing an opposite spray crystallization method for faster and safer production of ultrafine explosive cocrystals.
- Characterization techniques like electron microscopy, differential thermal analysis, and X-ray diffraction were employed to analyze the samples, leading to an optimization of the spray crystallization parameters such as temperature, feed ratio, and method.
- Results showed that using acetone as a cosolvent and maintaining a spraying temperature of 30 °C with a 1:1 feeding ratio enhanced cocrystal formation, resulting in smaller particle sizes (~10 μm) and reduced mechanical sensitivity, making the process simpler and safer.
Interaction, Insensitivity and Thermal Conductivity of CL-20/TNT-Based Polymer-Bonded Explosives through Molecular Dynamics Simulation.
Int J Mol Sci
July 2023
Molecules and Materials Computation Institute, School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Binders mixed with explosives to form polymer-bonded explosives (PBXs) can reduce the sensitivity of the base explosive by improving interfacial interactions. The interface formed between the binder and matrix explosive also affects the thermal conductivity. Low thermal conductivity may result in localized heat concentration inside the PBXs, causing the detonation of the explosive.
View Article and Find Full Text PDFMechanism of the Impact-Sensitivity Reduction of Energetic CL-20/TNT Cocrystals: A Nonequilibrium Molecular Dynamics Study.
Polymers (Basel)
March 2023
Henan Key Laboratory of Crystalline Molecular Functional Materials, Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
High-energy low-sensitivity explosives are research objectives in the field of energetic materials, and the formation of cocrystals is an important method to improve the safety of explosives. However, the sensitivity reduction mechanism of cocrystal explosives is still unclear. In this study, CL-20/TNT, CL-20 and TNT crystals were taken as research objects.
View Article and Find Full Text PDFneural network MD simulation of thermal decomposition of a high energy material CL-20/TNT.
Phys Chem Chem Phys
May 2022
Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, China.
CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane, also known as HNIW) is one of the most powerful energetic materials. However, its high sensitivity to environmental stimuli greatly reduces its safety and severely limits its application. In this work, based neural network potential (NNP) energy surfaces for both β-CL-20 and CL-20/TNT co-crystals were constructed.
View Article and Find Full Text PDFUsing the molecular dynamics method based on the ReaxFF force field and combining it with the multi-scale shock technique, the physical and chemical change processes of CL-20/TNT co-crystals under shock loading were studied. Shock waves with velocities of 7, 8, 9 km s were applied to CL-20/TNT co-crystals along the , , and directions. The anisotropy brought by the co-crystal structure was analyzed.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!