Within the constraints of density functional theory(UB3LYP/6-311++G(d,p)),RDX/Al and RDX/2Al composites are investigated,considering various multiplicity states(singlet and triplet states).Depending on the localizatio...Within the constraints of density functional theory(UB3LYP/6-311++G(d,p)),RDX/Al and RDX/2Al composites are investigated,considering various multiplicity states(singlet and triplet states).Depending on the localization of Al atom(s)in space and multiplicity of the composite systems,the structure of RDX undergoes various degrees of perturbations.It has been shown that the presence of Al atoms affects the bond lengths,electron population as well as the HOMO and LUMO energies and the inter frontier molecular orbital energy gap of RDX.All these perturbations are thought to affect ballistic properties of the explosive molecule RDX.展开更多
Six fully optimized geometries of urea nitrate cation and RDX complexes have been obtained with DFT-B3LYP and MP2 methods at the 6-311++G** level. The intermolecular interaction energies have been calculated with ...Six fully optimized geometries of urea nitrate cation and RDX complexes have been obtained with DFT-B3LYP and MP2 methods at the 6-311++G** level. The intermolecular interaction energies have been calculated with basis set superposition error (BSSE) and zero point energy (ZPE) correction. The nature of intermolecular interaction has been revealed by the analysis of AIM and NBO. The results indicate that the greatest binding energy of urea nitrate with RDX is –82.47kJ/mol. The O–H…O and N–H…O hydrogen bonds are important intermolecular interactions of urea nitrate cation with RDX, and the origin of hydrogen bonds is the oxygen atom offering its lone-pair electrons to the σ(O-H)* or σ(O-H)* antibonding orbital. The intermolecular interactions strengthen the N–NO2 bond, leading to the reduced sensitivity of urea nitrate and RDX mixture explosive.展开更多
The composites of certain nitramine type explosives,TETRYL,RDX and EDNA,with proton in vacuum have been considered within the constraints of density functional theory at the level of B3LYP/6-31++G(d,p)(restricted and ...The composites of certain nitramine type explosives,TETRYL,RDX and EDNA,with proton in vacuum have been considered within the constraints of density functional theory at the level of B3LYP/6-31++G(d,p)(restricted and unrestricted).The results indicate that unexpectedly hydrogen molecule production occurs by the interaction of proton and a hydrogen of CH3(TETRYL)and CH2(RDX and EDNA)groups.As a result,a carbocation is generated on the explosive molecules.Thereafter,TETRYL which potentially has many protonation sites were investigated in more detail in vacuum and aqueous conditions.The data reveals that the composite system(TETRYL+proton)is less stable than TETRYL protonated on nitramine NH or oxygen of the nitro groups.展开更多
文摘Within the constraints of density functional theory(UB3LYP/6-311++G(d,p)),RDX/Al and RDX/2Al composites are investigated,considering various multiplicity states(singlet and triplet states).Depending on the localization of Al atom(s)in space and multiplicity of the composite systems,the structure of RDX undergoes various degrees of perturbations.It has been shown that the presence of Al atoms affects the bond lengths,electron population as well as the HOMO and LUMO energies and the inter frontier molecular orbital energy gap of RDX.All these perturbations are thought to affect ballistic properties of the explosive molecule RDX.
文摘Six fully optimized geometries of urea nitrate cation and RDX complexes have been obtained with DFT-B3LYP and MP2 methods at the 6-311++G** level. The intermolecular interaction energies have been calculated with basis set superposition error (BSSE) and zero point energy (ZPE) correction. The nature of intermolecular interaction has been revealed by the analysis of AIM and NBO. The results indicate that the greatest binding energy of urea nitrate with RDX is –82.47kJ/mol. The O–H…O and N–H…O hydrogen bonds are important intermolecular interactions of urea nitrate cation with RDX, and the origin of hydrogen bonds is the oxygen atom offering its lone-pair electrons to the σ(O-H)* or σ(O-H)* antibonding orbital. The intermolecular interactions strengthen the N–NO2 bond, leading to the reduced sensitivity of urea nitrate and RDX mixture explosive.
文摘The composites of certain nitramine type explosives,TETRYL,RDX and EDNA,with proton in vacuum have been considered within the constraints of density functional theory at the level of B3LYP/6-31++G(d,p)(restricted and unrestricted).The results indicate that unexpectedly hydrogen molecule production occurs by the interaction of proton and a hydrogen of CH3(TETRYL)and CH2(RDX and EDNA)groups.As a result,a carbocation is generated on the explosive molecules.Thereafter,TETRYL which potentially has many protonation sites were investigated in more detail in vacuum and aqueous conditions.The data reveals that the composite system(TETRYL+proton)is less stable than TETRYL protonated on nitramine NH or oxygen of the nitro groups.