Pressure produces closely packed,high-density materials,thereby providing a promising strategy to obtain high-energy-density materials.However,new phases or structures of energetic materials at high pressure are often...Pressure produces closely packed,high-density materials,thereby providing a promising strategy to obtain high-energy-density materials.However,new phases or structures of energetic materials at high pressure are often not quenchable under ambient conditions.In this work,high-pressure topochemical methodology is first introduced for the preparation of stable energetic materials under ambient conditions.A pressure-induced polymerizable energetic material named PIP-1 is designed and prepared.The experimental measurements demonstrate that the polymerization of PIP-1 is caused by the breakage of C≡C bonds and the generation of C=C bonds.In accord with the experimental results,density functional theory calculations further revealed that the monomer PIP-1 is polymerized to generate 1D PIP-1 tape,and the density of polymerized PIP-1 is increased by 4.9%upon decompression.The successful realization of high-energy-density structure using high pressure showcases a new design strategy for advanced polymerizable energetic materials.展开更多
Pressure, as a thermodynamic parameter, provides an appropriate method to detect weak intermolecular interactions. The C–H···H–B dihydrogen bond is so weak that the experimental evidence of this inter...Pressure, as a thermodynamic parameter, provides an appropriate method to detect weak intermolecular interactions. The C–H···H–B dihydrogen bond is so weak that the experimental evidence of this interaction is still limited. A combination of in situ high pressure Raman spectra and angle-dispersive X-ray diffraction(ADXRD) experiments was utilized to explore the dihydrogen bonds in dimethylamine borane(DMAB). Both Raman and ADXRD measurements suggested that the crystal structure of DMAB is stable in the pressure region from 1 atm(1 atm=1.01325×10~5 Pa) to 0.54 GPa. The red shift of CH stretching and CH_3 distortion modes gave strong evidence for the existence of C–H···H–B dihydrogen bonds. Further analysis of Raman spectra and Hirshfeld surface confirmed our proposal. This work provided a deeper understanding of dihydrogen bonds.And we wish that high pressure could be applied to identify other unconfirmed hydrogen or dihydrogen bond.展开更多
基金supported by the Presidential Foundation of CAEP(grant no.YZJJLX2019006)the National Science Foundation of China(grant nos.22075259 and 22175157).
文摘Pressure produces closely packed,high-density materials,thereby providing a promising strategy to obtain high-energy-density materials.However,new phases or structures of energetic materials at high pressure are often not quenchable under ambient conditions.In this work,high-pressure topochemical methodology is first introduced for the preparation of stable energetic materials under ambient conditions.A pressure-induced polymerizable energetic material named PIP-1 is designed and prepared.The experimental measurements demonstrate that the polymerization of PIP-1 is caused by the breakage of C≡C bonds and the generation of C=C bonds.In accord with the experimental results,density functional theory calculations further revealed that the monomer PIP-1 is polymerized to generate 1D PIP-1 tape,and the density of polymerized PIP-1 is increased by 4.9%upon decompression.The successful realization of high-energy-density structure using high pressure showcases a new design strategy for advanced polymerizable energetic materials.
基金supported by the National Natural Science Foundation of China(21725304,21673100,91227202,11774120,11774125)the Chang Jiang Scholars Program of China(T2016051)+3 种基金Changbai Mountain Scholars Program(2013007)Program for Innovative Research Team(in Science and Technology)in University of Jilin Province and Graduate Innovation Fund of Jilin University(2017050)ADXRD experiments were performed at Beijing Synchrotron Radiation Facility(4W2 beamline)which is supported by Chinese Academy of Sciences(KJCX2-SW-N20,KJCX2-SW-N03)
文摘Pressure, as a thermodynamic parameter, provides an appropriate method to detect weak intermolecular interactions. The C–H···H–B dihydrogen bond is so weak that the experimental evidence of this interaction is still limited. A combination of in situ high pressure Raman spectra and angle-dispersive X-ray diffraction(ADXRD) experiments was utilized to explore the dihydrogen bonds in dimethylamine borane(DMAB). Both Raman and ADXRD measurements suggested that the crystal structure of DMAB is stable in the pressure region from 1 atm(1 atm=1.01325×10~5 Pa) to 0.54 GPa. The red shift of CH stretching and CH_3 distortion modes gave strong evidence for the existence of C–H···H–B dihydrogen bonds. Further analysis of Raman spectra and Hirshfeld surface confirmed our proposal. This work provided a deeper understanding of dihydrogen bonds.And we wish that high pressure could be applied to identify other unconfirmed hydrogen or dihydrogen bond.