Five polymer bonded explosives(PBXs)with the base explosive epsilon-CL-20(hexanitrohexaazaisowurtzi-tane),the most important high energy density compound(HEDC),and five polymer binders(Estane 5703,GAP,HTPB,PEG,and F_(...Five polymer bonded explosives(PBXs)with the base explosive epsilon-CL-20(hexanitrohexaazaisowurtzi-tane),the most important high energy density compound(HEDC),and five polymer binders(Estane 5703,GAP,HTPB,PEG,and F_(2314))were constructed.Molecular dynamics(MD)method was employed to investigate their binding energies(E_(bind))< compatibility,safety,mechanical properties,and energetic properties.The information and rules were reported for choosing better binders and guiding formulation design of high energy density material(HEDM).According to the calculated binding energies,the ordering of compatibility and stability of the five PBXs was predicted as epsilon-CL-20/PEG < epsilon-CL-20/ Estane5703 ≈ epsilon-CL-20/GAP < epsilon-CL-20/HTPB < epsilon-CL-20/F_(2314).By pair correlation function g(r)analyses,hydrogen bonds and vdw are found to be the main interactions between the two components.The elasticity and isotropy of PBXs based epsilon-CL-20 can be obviously improved more than pure epsilon-CL-20 crystal.It is not by changing the molecular structures of epsilon-CL-20 for each binder to affect the sensitivity.The safety and energetic properties of these PBXs are mainly influenced by the thermal capability(C_p^(deg))and density(p)of binders,respectively.展开更多
Using geometrical optimization and DFT method at the B3LYP/6-31G （d） level, nineteen equilibrium geometries were identified, and three transition states of dissociation reaction of C3O6 clusters were also found. The...Using geometrical optimization and DFT method at the B3LYP/6-31G （d） level, nineteen equilibrium geometries were identified, and three transition states of dissociation reaction of C3O6 clusters were also found. The vibrational frequencies and intrinsic reaction coordinate （IRC） verification at the same level were computed to verify the transitions. And then we calculated the dissociation energies and analyzed the dissociation channels. The computational results show that the dissociation energies of C3O6 isomers relative to three CO2 are between 1.509 × 103 and 10.61 × 10^3 kJ·kg^-1, and the energy barriers of the reactions are 92.857, 131.138 and 185.793 kJ·mol^-1. Both the high dissociation energies and high energy barriers show that C3O6 clusters studied in this paper are stable enough to be used as high-energy-density materials.展开更多
The cyclo-N_(6)anion is a total nitrogen unit with higher nitrogen content than cyclo-N^(-)_(5).However,the low decomposition barrier of cyclo-N_(6)anions hinders its application as a high energy density material(HEDM...The cyclo-N_(6)anion is a total nitrogen unit with higher nitrogen content than cyclo-N^(-)_(5).However,the low decomposition barrier of cyclo-N_(6)anions hinders its application as a high energy density material(HEDM).Using first-principles calculations,we reveal that the covalent components that enhance the interaction between the cyclo-N_(6)anion and the cation can effectively improve the stability of cyclo-N_(6)anions.The actinide metals(Th,Pa,U)are selected as suitable cations.Further electronic structure analysis showed that the charge transfer from the actinide metal to cyclo-N_(6)anions resulted in a strong covalent bond,which promoted the stability of the cyclo-N_(6)anion in the Th(N_(6)),Pa(N_(6)),and U(N_(6))structure.This discovery is helpful for the rational design and synthesis of new HEDMs.展开更多
基金Supported by the National Natural Science Foundation of China (Grant No. 10176012)the Important Foundation of China Academy of Engineering Physics (CAEP, 2004Z0503) and 973 Program of China
文摘Five polymer bonded explosives(PBXs)with the base explosive epsilon-CL-20(hexanitrohexaazaisowurtzi-tane),the most important high energy density compound(HEDC),and five polymer binders(Estane 5703,GAP,HTPB,PEG,and F_(2314))were constructed.Molecular dynamics(MD)method was employed to investigate their binding energies(E_(bind))< compatibility,safety,mechanical properties,and energetic properties.The information and rules were reported for choosing better binders and guiding formulation design of high energy density material(HEDM).According to the calculated binding energies,the ordering of compatibility and stability of the five PBXs was predicted as epsilon-CL-20/PEG < epsilon-CL-20/ Estane5703 ≈ epsilon-CL-20/GAP < epsilon-CL-20/HTPB < epsilon-CL-20/F_(2314).By pair correlation function g(r)analyses,hydrogen bonds and vdw are found to be the main interactions between the two components.The elasticity and isotropy of PBXs based epsilon-CL-20 can be obviously improved more than pure epsilon-CL-20 crystal.It is not by changing the molecular structures of epsilon-CL-20 for each binder to affect the sensitivity.The safety and energetic properties of these PBXs are mainly influenced by the thermal capability(C_p^(deg))and density(p)of binders,respectively.
基金Supported by the Natural Science Foundation of Shandong Province (No. Y2006B24 and Y2008B33)
文摘Using geometrical optimization and DFT method at the B3LYP/6-31G （d） level, nineteen equilibrium geometries were identified, and three transition states of dissociation reaction of C3O6 clusters were also found. The vibrational frequencies and intrinsic reaction coordinate （IRC） verification at the same level were computed to verify the transitions. And then we calculated the dissociation energies and analyzed the dissociation channels. The computational results show that the dissociation energies of C3O6 isomers relative to three CO2 are between 1.509 × 103 and 10.61 × 10^3 kJ·kg^-1, and the energy barriers of the reactions are 92.857, 131.138 and 185.793 kJ·mol^-1. Both the high dissociation energies and high energy barriers show that C3O6 clusters studied in this paper are stable enough to be used as high-energy-density materials.
基金National Natural Science Foundation of China(No.11805157)Sichuan Provincial Department of Science and Technology Application Fundamental Research,China(No.2017JY0146)+1 种基金China West Normal University Scientific Research Innovation Team Project(No.CXTD2016-2)China West Normal University Talent Research Fund Project(No.CXTD2017-10)。
文摘The cyclo-N_(6)anion is a total nitrogen unit with higher nitrogen content than cyclo-N^(-)_(5).However,the low decomposition barrier of cyclo-N_(6)anions hinders its application as a high energy density material(HEDM).Using first-principles calculations,we reveal that the covalent components that enhance the interaction between the cyclo-N_(6)anion and the cation can effectively improve the stability of cyclo-N_(6)anions.The actinide metals(Th,Pa,U)are selected as suitable cations.Further electronic structure analysis showed that the charge transfer from the actinide metal to cyclo-N_(6)anions resulted in a strong covalent bond,which promoted the stability of the cyclo-N_(6)anion in the Th(N_(6)),Pa(N_(6)),and U(N_(6))structure.This discovery is helpful for the rational design and synthesis of new HEDMs.
