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1.
The structures of hydrazinium dinitramide (HDN) in the gas phase and in aqueous solution have been studied at different levels of theory by using quantum chemistry. The intramolecular hydrogen‐bond interactions in HDN were studied by employing the quantum theory of atoms in molecules (QTAIM), as well as those in ammonium dinitramide (ADN), hydrazinium nitroformate (HNF), and ammonium nitroformate (ANF) for comparison. The results showed that HDN possessed the strongest hydrogen bonds, with the largest hydrogen‐bond energy (?47.95 kJ mol?1) and the largest total hydrogen‐bond energy (?60.29 kJ mol?1). In addition, the charge transfer between the cation and the anion, the binding energy, the energy difference between the frontier orbitals, and the second‐order perturbation energy of HDN were all the largest among the investigated compounds. These strongest intramolecular interactions accounted for the highest decomposition temperature of HDN among all four compounds. The IR spectra in the gas phase and in aqueous solution were very different and showed the significant influence of the solvent. The UV spectrum showed the strongest absorption at about 253 nm. An orbital‐interaction diagram demonstrated that the transition of electrons mainly happened inside the anion of HDN. The detonation velocity (D=8.34 km s?1) and detonation pressure (P=30.18 GPa) of HDN were both higher than those of ADN (D=7.55 km s?1 and P=24.83 GPa). The composite explosive HDN/CL‐20 with the weight ratio wCL?20/wHDN=0.388:0.612 showed the best performance (D=9.36 km s?1, P=39.82 GPa), which was close to that of CL‐20 (D=9.73 km s?1, P=45.19 GPa) and slightly better than that of the composite explosive ADN/CL‐20 (wCL?20/wADN=0.298:0.702, D=9.34 km s?1, P=39.63 GPa).  相似文献   

2.
Bis(4‐nitraminofurazanyl‐3‐azoxy)azofurazan ( 1 ) and ten of its energetic salts were prepared and fully characterized. Computational analysis based on isochemical shielding surface and trigger bond dissociation enthalpy provide a better understanding of the thermal stabilities for nitramine‐furazans. These energetic compounds exhibit good densities, high heats of formation, and excellent detonation velocity and pressure. Some representative compounds, for example, 1 (vD: 9541 m s?1; P: 40.5 GPa), and 4 (vD: 9256 m s?1; P: 38.0 GPa) exhibit excellent detonation performances, which are comparable with current high explosives such as RDX (vD: 8724 m s?1; P: 35.2 GPa) and HMX (vD: 9059 m s?1; P: 39.2 GPa).  相似文献   

3.
A new class of N,N′‐ethylene‐bridged bis(nitropyrazoles) was synthesized and fully characterized. The highly efficient formation of the N,N′‐ethylene bridge was accomplished using dibromoethane and ammonium or potassium pyrazolate. Further functional‐group transformations of diaminobis(pyrazole) and dichlorobis(pyrazole) gave rise to diversified derivatives, including dinitramino‐, diazido‐ and hexanitrobis(pyrazole). Single‐crystal X‐ray diffractions were obtained for hexanitro and diazido derivatives to illustrate the structural characteristics. Heats of formation and detonation performance were calculated by using Gaussian 03 and EXPLO5 v6.01 programs, respectively. Because of the different functionalized groups, the impact and friction sensitivities of these new compounds range from insensitive to sensitive. Among them, the hexanitro derivative displays the most promising overall energetic properties (density (ρ)=1.84 g cm?3; decomposition temperature (Td)=250 °C; detonation pressure (P)=34.1 GPa; detonation velocity (vD)=8759 m s?1; impact sensitivity (IS)=25 J; friction sensitivity (FS)=160 N), which is competitive with those of 1,3,5‐trinitrotriazacyclohexane (ρ=1.80 g cm?3; Td=205 °C; P=35.0 GPa; vD=8762 m s?1; IS=7 J; FS=120 N).  相似文献   

4.
Bis (1, 5‐diamino‐4‐methyl‐tetrazolium) azotetrazolate ( BMDATZT ) was synthesized with high yield in this work. The yield is 97.46%. The structure was characterized by IR, 1H NMR, and MS. The single crystal of BMDATZT?2H2O was first cultivated. The heat of formation, detonation pressure, and detonation velocity were first calculated. The crystalline density of BMDATZT?2H2O is 1.573 g/cm3. BMDATZT has high detonation pressure and detonation velocity (P =25.06 GPa, D = 7.805 km s?1), which are higher than those of 2,4,6‐Trinitrotoluene (TNT). Its thermal and mechanical sensitivities are moderate. Therefore, it is a kind of insensitive nitrogen‐rich energetic ionic salt with good performance, and it has potential application prospect in gas generating agent, explosive and solid propellant.  相似文献   

5.
The amino, azido, nitro, and nitrogen‐rich azole substituted derivatives of 1H‐benzotriazole have been synthesized for energetic material applications. The synthesized compounds were fully characterized by 1H and 13C NMR spectroscopy, IR, MS, and elemental analysis. 5‐Chloro‐4‐nitro‐1H‐benzo[1,2,3]triazole ( 2 ) and 5‐azido‐4,6‐dinitro‐1H‐benzo[1,2,3]triazole ( 7 ) crystallize in the Pca21 (orthorhombic) and P21/c (monoclinic) space group, respectively, as determined by single‐crystal X‐ray diffraction. Their densities are 1.71 and 1.77 g cm?3, respectively. The calculated densities of the other compounds range between 1.61 and 1.98 g cm?3. The detonation velocity (D) values calculated for these synthesized compounds range from 5.45 to 8.06 km s?1, and the detonation pressure (P) ranges from 12.35 to 28 GPa.  相似文献   

6.
1,5‐Diamino‐4‐methyltetrazolium 5‐nitrotetrazolate ( 2b ) was synthesized in high yield from 1,5‐diamino‐4‐methyltetrazolium iodide ( 2a ) and highly sensitive silver 5‐nitrotetrazolate (AgNT). A safer synthesis, suitable for scale‐up, is introduced involving reaction of the previously unreported 1‐amino‐5‐imino‐4‐methyltetrazole free base ( 2 ) with ammonium 5‐nitrotetrazolate. Both new compounds ( 2 and 2b ) were fully characterized using vibrational (IR and Raman) and multinuclear NMR spectroscopy (1H, 13C, 14N, 15N), elemental analysis and single crystal X‐ray diffraction. The hydrogen‐bonding networks of both materials are described in terms of their graph‐sets. Compound 2b is hydrolytically stable with a high melting point and concomitant decomposition at 160 °C. The sensitivity of the energetic salt 2b towards impact (>30 J) and friction (>360 N) was tested. The constant volume energy of combustion (ΔcU) of 2b was measured experimentally using bomb calorimetry. In addition, the detonation parameters (detonation pressure and velocity) of the nitrotetrazolate salt were calculated from the energy of formation, the crystal density and the molecular formula using the EXPLO5 computer code (P = 15.5·GPa, D = 6749 m s?1) and are similar to that of TNT and nitroguanidine making 2b of prospective interest in propellant charge formulations or, in combination with a suitable oxidizer, as a solid propellant.  相似文献   

7.
2-Azido-4-nitroimidazole and its derivatives have been synthesized for energetic material applications. The synthesized compounds were fully characterized by 1H, 13C NMR spectroscopy and elemental analysis. Most of them were determined by single crystal X-ray diffraction. The calculated densities of the compounds range between 1.71 and 1.92 g,cm-3. The calculated detonation pressures (P) for these derivatives fall in the range of 25.17 to 32.62 GPa and the detonation velocities (D) are distributed from 7.65 to 8.55 km·s-1.  相似文献   

8.
Bis(5‐amino‐1,2,4‐triazol‐3‐yl)methane (BATZM, C5H8N8) was synthesized and its crystal structure characterized by single‐crystal X‐ray diffraction; it belongs to the space group Fdd2 (orthorhombic) with Z = 8. The structure of BATZM can be described as a V‐shaped molecule with reasonable chemical geometry and no disorder. The specific molar heat capacity (Cp,m) of BATZM was determined using the continuous Cp mode of a microcalorimeter and theoretical calculations, and the Cp,m value is 211.19 J K?1 mol?1 at 298.15 K. The relative deviations between the theoretical and experimental values of Cp,m, HTH298.15K and STS298.15K of BATZM are almost equivalent at each temperature. The detonation velocity (D) and detonation pressure (P) of BATZM were estimated using the nitrogen equivalent equation according to the experimental density; BATZM has a higher detonation velocity (7954.87 ± 3.29 m s?1) and detonation pressure (25.72 ± 0.03 GPa) than TNT.  相似文献   

9.
In this study, we explore the possibility that fused polynitrodiazoles act as high energy density materials. Density functional theory calculations at the B3LYP/aug‐cc‐pVDZ level were performed to predict the structure, energy of explosion (≈1.68 kcal g?1), density (≈1.98 g cm?3), detonation velocity (≈9.50 km s?1), and detonation pressure (≈41.50 GPa) of model molecules. The predicted properties have been found to be promising compared with 3,4,5‐trinitro‐1H‐pyrazole, 1,3,5‐trinitro‐1,3,5‐triazinane, and octahydro‐1,3,5,7‐tetranitro‐l,3,5,7‐tetraazocane. The nature of azoles of the molecule presumably determines the geometry, stability, sensitivity, density, and detonation performance. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011  相似文献   

10.
1,3‐Dimethyl‐5‐amino‐1H‐tetrazolium 5‐nitrotetrazolate ( 5b ) was synthesized in high yield from 1,4‐dimethyl‐5‐amino‐1H‐tetrazolium iodide ( 5a ) and silver 5‐nitrotetrazolate. Both new compounds ( 5a and 5b ) were characterized using vibrational (IR and Raman) and multinuclear NMR spectroscopy (1H, 13C and 15N), elemental analysis and single‐crystal X‐ray diffraction. 5a crystallizes in an orthorhombic cell: Pbca, a = 11.5016(4), b = 13.7744(5), c = 13.7744(5) Å, V = 1638.2(1) Å3, Z = 8, ρ = 1.955 g cm?3, R1 = 0.0210 (F > 4σ(F)), wR2 (all data) = 0.0542; whereas 5b crystallizes in a monoclinic cell: C1c, a = 14.5228(8), b = 5.0347(2), c = 13.7217(7) Å, β = 112.11(1)°, V = 929.6(2) Å3, Z = 4, ρ = 1.630 g cm?3, R1 = 0.0279 (F > 4σ(F)), wR2 (all data) = 0.0585. The sensitivity of 5b to classical stimuli was determined by using standard BAM tests and its thermal stability was assessed by DSC measurements. In addition, its heat of combustion was determined by bomb calorimetry measurements. The EXPLO5 was used to calculate the detonation pressure (P) and velocity (D) of 5b (P = 13.3 GPa and D = 6379 m s?1), as well as those of its mixtures with ammonium nitrate (P = 23.2 GPa and D = 7862 m s?1) and ammonium dinitramide (P = 29.6 GPa and D = 8594 m s?1). Compound 5b is a hydrolytically stable solid with a high melting point (160 °C) and thermally stable to 190 °C with a very low sensitivity to friction (>360 N) and impact (>30 J) and good performance in combination with an oxidizer making it of interest in new environmentally friendly, insensitive explosive formulations.  相似文献   

11.
Bis(5‐amino‐1,2,4‐triazol‐4‐ium‐3‐yl)methane dichloride (BATZM·Cl2 or C5H10N82+·2Cl?) was synthesized and crystallized, and the crystal structure was characterized by single‐crystal X‐ray diffraction; it belongs to the space group C2/c (monoclinic) with Z = 4. The structure of BATZM·Cl2 can be described as a V‐shaped molecule with reasonable chemical geometry and no disorder, and its one‐dimensional structure can be described as a rhombic helix. The specific molar heat capacity (Cp,m) of BATZM·Cl2 was determined using the continuous Cp mode of a microcalorimeter and theoretical calculations, and the Cp,m value is 276.18 J K?1 mol?1 at 298.15 K. The relative deviations between the theoretical and experimental values of Cp,m, HTH298.15K and STS298.15K of BATZM·Cl2 are almost equivalent at each temperature. The detonation velocity (D) and detonation pressure (P) of BATZM·Cl2 were estimated using the nitrogen equivalent equation according to the experimental density; BATZM·Cl2 has a higher detonation velocity (7143.60 ± 3.66 m s?1) and detonation pressure (21.49 ± 0.03 GPa) than TNT. The above results for BATZM·Cl2 are compared with those of bis(5‐amino‐1,2,4‐triazol‐3‐yl)methane (BATZM) and the effect of salt formation on them is discussed.  相似文献   

12.
Potassium 4,5‐bis(dinitromethyl)furoxanate was synthesized readily from cyanoacetic acid. It was characterized by IR spectroscopy, elemental analysis, NMR spectroscopy, and differential scanning calorimetry (DSC), and the structure was confirmed by X‐ray single‐crystal diffraction. Its positive oxygen balance, high density (2.130 g cm?3), sensitivity (IS=2 J, FS=5 N), and calculated heat of formation (?421.0 kJ mol?1), combined with its calculated superior detonation performance (D=7759.0 m s?1, P=27.3 GPa), make it a competitive replacement as a green primary explosive.  相似文献   

13.
High density energetic salts containing nitrogen‐rich cations and the nitranilic anion were readily synthesized in high yield by metathesis reactions of sodium nitranilate 2 and an appropriate halide. All of the new compounds were fully characterized by elemental, spectral (IR, 1H, 13C NMR), and thermal (DSC) analyses. The structure of hydrazinium nitranilate ( 4 ) was also determined by single‐crystal X‐ray analysis. The high symmetry and oxygen content of the anion give these salts extensive hydrogen bonding capability which further results in the high densities, low water solubilities, and high thermal stabilities (Td> 200 °C) of these compounds. Theoretical performance calculations were carried out by using Gaussian 03 and Cheetah 5.0. The calculated detonation pressures (P) for these new salts fall between 17.5 GPa ( 10 ) and 31.7 GPa ( 4 ), and the detonation velocities (νD) range between 7022 m s?1 ( 13 ) and 8638 m s?1 ( 4 ).  相似文献   

14.
The title compound, 1,3‐dinitramino‐2‐nitroxy‐propane ( 1 ) was prepared in high yield (85 %) and characterized by multinuclear NMR (1H, 13C, 14N) and vibrational (IR, Raman) spectroscopy. The molecular structure in the solid state was elucidated by single crystal X‐ray diffraction. 1 crystallizes in the orthorhombic space group Pnma with a crystal density of ρ = 1.798 g cm?3. Compound 1 melts at 166 °C and decomposes at 168 °C. The impact (7 J), friction (96 N) and electrostatic discharge sensitivities (0.6 J) were determined experimentally. The detonation parameters of 1 were calculated using a combined quantum chemical (CBS‐4M) calculation and a chemical equilibrium calculation based on the steady‐state model of detonation: Q = ?5998 kJ kg?1, P = 339 kbar, D = 8895 m s?1. The experimentally determined detonation velocity (fiber optic method) agrees well with the calculated values. In comparison with picric acid (PA) and nitropenta (PETN), compound 1 shows superior detonation characteristics when detonated in a confined space.  相似文献   

15.
In recent years, cocrystallization has emerged as an effective way of tuning the properties of compounds and has been widely used in the field of energetic materials. In this study, we have prepared two novel cocrystals of CL‐20 and methylimidazole, including a 1:2 CL‐20 / 2‐mercapto‐1‐methylimidazole ( 1 ) and a 1:4 CL‐20 / 4‐methyl‐5‐nitroimidazole ( 2 ). Cocrystal 1 has good physical and detonation properties (ρ1 = 1.652 g · cm–3, D1 = 7073 m · s–1, P1 = 21.6 GPa); however, cocrystal 2 shows higher properties (ρ2 = 1.680 g · cm–3, D2 = 7945 m · s–1, P2 = 27.4 GPa). The performance of both cocrystals is better than those of TNT. Thermal performance suggests that both the cocrystals have moderate thermal stabilities. Cocrystal 1 decomposes at 164.9 °C and cocrystal 2 has an exothermic peak at 221 °C. Both cocrystals are insensitive energetic explosives (IS > 40 J, FS > 360 N). Methylimidazole compounds are rarely used as coformers to form cocrystals with CL‐20, which possess good properties for a range of potential applications. Herein, we provide new possible directions for enriching cocrystal speciation.  相似文献   

16.
A new family of bridged bis(multinitro-triazole) was designed and investigated using the density functional theory method. The density, oxygen balance, heat of formation, detonation performance, and impact sensitivity were calculated systematically. The results show that the multinitromethyl groups play an important role in increasing densities. At the same time, different bridged groups present diverse performances with high density (1.86-1.96 g·cm−3), excellent detonation properties (V = 8.72 km·s−1-9.20 km·s−1; P = 34.54 GPa-39.49 GPa), outstanding oxygen balance (0%-11.59%), and acceptably impact sensitivity. Especially, tetrazine (M7)-bridged and diaminofurazan (M9)-bridged groups are very helpful for enhancing their detonation performance (V(M7) = 9.12 km·s−1, P(M7) = 38.51 GPa; V(M9) = 9.20 km·s−1, P(M9) = 39.49 GPa), respectively, which are better than RDX. They could be seen as the potential candidates of high energy density materials (HEDMs).  相似文献   

17.
Rate constants for the reactions of Cl atoms with two cyclic dienes, 1,4‐cyclohexadiene and 1,5‐cyclooctadiene, have been determined, at 298 K and 800 Torr of N2, using the relative rate method, with n‐hexane and 1‐butene as reference molecules. The concentrations of the organics are followed by gas chromatographic analysis. The ratios of the rate constants of reactions of Cl atoms with 1,4‐cyclohexadiene and 1,5‐cyclooctadiene to that with n‐hexane are measured to be 1.29 ± 0.06 and 2.19 ± 0.32, respectively. The corresponding ratios with respect to 1‐butene are 1.50 ± 0.16 and 2.36 ± 0.38. The absolute values of the rate constants of the reaction of Cl atom with n‐hexane and 1‐butene are considered as (3.15 ± 0.40) × 10?10 and (3.21 ± 0.40) × 10? 10 cm3 molecule?1s?1, respectively. With these, the calculated values are k(Cl + 1,4‐cyclohexadiene) = (4.06 ± 0.55) × 10?10 and k(Cl + 1,5‐cyclooctadiene) = (6.90 ± 1.33) × 10?10 cm3 molecule?1 s?1 with respect to n‐hexane. The rate constants determined with respect to 1‐butene are marginally higher, k(Cl + 1,4‐cyclohexadiene) = (4.82 ± 0.80) × 10? 10 and k(Cl + 1,5‐cyclooctadiene) = (7.58 ± 1.55) × 10? 10 cm3 molecule?1 s?1. The experiments for each molecule were repeated three to five times, and the slopes and the rate constants given above are the average values of these measurements, with 2σ as the quoted error, including the error in the reference rate constant. The relative rate ratios of 1,4‐cyclohexadiene with both the reference molecules are found to be higher in the presence of oxygen, and a marginal increase is observed in the case of 1,5‐cyclooctadiene. Benzene is identified as one major product in the case of 1,4‐cyclohexadiene. Considering that the cyclohexadienyl radical, a product of the hydrogen abstraction reaction, is quantitatively converted to benzene in the presence of oxygen, the fraction of Cl atoms that reacts by abstraction is estimated to be 0.30 ± 0.04. The atmospheric implications of the results are discussed. © 2011 Wiley Periodicals, Inc. Int J Chem Kinet 43: 431–440, 2011  相似文献   

18.
The synthesis of a series of nitroxy‐ and azido‐functionalized compounds, based on 4‐amino‐3,5‐di(hydroxymethyl)‐1,2,4‐triazole, for possible use as an energetic plasticizers is described. All compounds were fully characterized. Two of them were further confirmed by X‐ray single crystal diffraction. Energetic performance was calculated by using EXPLO5 v6.01 based on calculated heats of formation (Gaussian 03) and experimentally determined densities at 25 °C. The results show that the nitration product 1‐nitro‐3,5‐di(nitroxymethyl)‐1,2,4‐triazole, containing a nitro group and two nitroxy groups, exhibits good detonation properties (D=8574 m s?1, P=32.7 GPa). In addition, its low melting point makes it very attractive as an energetic plasticizer in solid propellants.  相似文献   

19.
Ammonia borane (AB) is used as a combustion agent to improve the properties of high explosives. The detonation velocity (Dv) and detonation pressure (P) of raw high explosives and of samples containing AB were calculated and compared. The detonation properties, impact sensitivities, thermal sensitivities, and thermal decomposition characteristics of high explosives containing AB were also measured. The results indicated that when the AB content was 20 wt‐%, the optimal detonation velocity and detonation pressure were achieved. Both the detonation velocity and detonation pressure of the high explosives containing AB were clearly increased compared with those of the raw high explosives. Moreover, the detonation velocities of high explosives containing AB were 7078 to 7423 m · s–1 and their density ranged from 1.570 to 1.589 g · cm–3. The detonation pressure ranged from 34.5 to 37 GPa and the average heat of detonation was 6688 J · g–1. Furthermore, the impact and thermal sensitivities were 170 cm and 613 K, respectively, whereas a slight change occurred in the thermal decomposition characteristics. These results suggest that AB can serve as a powerful combustible agent in energetic materials and improve the detonation properties and sensitivities of high explosives.  相似文献   

20.
N,N′‐Bis(difuroxano[3,4‐b:3′,4′‐d]phenyl)oxalic amide was synthesized via acylation, nitration, azidation, and pyrolysis‐denitrogenation from the starting materials of oxalyl chloride and 3,5‐dichloroaniline, under mild reaction conditions, with the yields of 81.0%, 82.0%, 86.0% and 81.7% respectively. The title compound and its precursors were characterized by 1H NMR, IR, MS, and elemental analysis. The title compound has a density of 1.92 g·cm?3 by a suspension method, a standard formation enthalpy of 979 kJ·mol?1 calculated by Gaussian programs, a detonation velocity of 8.17 km·s?1, and a detonation pressure of 31 GPa obtained by Kamlet Equation. The thermal decomposition reactions of the title compound at different heating rates were tested by differential scanning calorimetry (DSC). The kinetics parameters of the pyrolysis of the compound were calculated by Kissinger's method. The values of apparent activation energy (Ea) and pre‐exponential constant (A) were 226.7 kJ·mol?1 and 1023.17 s?1 respectively. It was presupposed that N,N′‐bis(difuroxano[3,4‐b:3′,4′‐d]phenyl)oxalic amide would be a promising high energetic explosive with low sensitivity.  相似文献   

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