物理学报2024，Vol.73Issue(19)：69-75,7.DOI:10.7498/aps.73.20240944
太赫兹光谱学研究CL-20/MTNP共晶振动特性
Research on vibrational features of CL-20/MTNP cocrystal by terahertz spectroscopy
摘要
Abstract
Cocrystals represent an effective method to manipulate the physicochemical properties of materials at a molecular level.However,understanding the relationship between their complex crystal structures and macroscopic properties is a challenge.In this paper,by using terahertz(THz)spectroscopy to characterize non-covalent interactions within crystals,the THz vibrational spectra of the CL-20/MTNP cocrystal are studied.Firstly,the THz spectra of CL-20,MTNP,and the CL-20/MTNP cocrystal are measured at room temperature.Both absorption positions and intensities of the cocrystals differ from those of their original components,confirming the unique advantage of terahertz spectroscopy in cocrystal identification.Secondly,the THz vibrational features of the three materials are calculated based on density functional theory(DFT).Then,the experimental absorptions are matched with the calculated vibrations.Furthermore,a vibrational decomposition method is employed to decompose the molecular vibrations into intermolecular and intramolecular vibrations.The vibrational variations of the cocrystal compared with its original components are analyzed.The results reveal that in the cocrystal,the intermolecular vibrational modes of both CL-20 and MTNP molecules have changed compared with their raw materials.This indicates that the non-covalent interactions in the cocrystal have changed the original intermolecular interactions of these molecules.Consequently,this enhancement promotes the heat transfer between MTNP and CL-20 molecules,thereby improving the thermal stability of the cocrystal.These findings in this study demonstrate that the THz vibrational spectroscopy technology helps establish a relationship between the molecular structure of cocrystal and its macroscopic properties.This research contributes to deepening our understanding of cocrystal systems and opens up a new way for designing and optimizing materials.关键词
太赫兹光谱/密度泛函理论/振动分解/CL-20共晶Key words
terahertz spectroscopy/density functional theory/vibrational decomposition/CL-20 cocrystal引用本文复制引用
刘泉澄,杨富,张祺,段勇威,邓琥,尚丽平..太赫兹光谱学研究CL-20/MTNP共晶振动特性[J].物理学报,2024,73(19):69-75,7.基金项目
国家自然科学基金(批准号:22305198)和西南科技大学博士基金(批准号:21ZX7143)资助的课题. Project supported by the National Natural Science Foundation of China(Grant No.22305198)and the Doctoral Foundation of Southwest University of Science and Technology,China(Grant No.21ZX7143). （批准号:22305198）
