764-05-6Relevant articles and documents
Kinetics and mechanism of the CN + NCO → NCN + CO reaction studied by experiment and theory
Tzeng, Shiang-Yang,Chen, Po-Hsueh,Wang, Niann S.,Lee,Xu,Lin
, p. 6314 - 6325 (2009)
The rate coefficients for the CN + NCO → NCN + CO reaction have been measured by a laser-photolysis/ laser-induced fluorescence technique in the temperature range of 254-353 K and the He pressures of 123-566 Torr. The CN radical was produced from the photolysis of BrCN at 193 nm, and the NCO radical from the CN + O2 reaction. The NCN radical was monitored by laser-induced fluorescence with a dye laser at 329.01 nm. The rate constants derived from kinetic modeling, with a negative temperature dependence but no pressure effect, can be expressed by k = (2.15 ± 0.70) × 10 -11 exp[(155 ± 92)/T]cm3 molecule-1 s-1, where the quoted errors are two standard deviations. The reaction mechanism and rate constant have also been theoretically predicted for the temperature range of 200-3000 K at He pressures ranging from 10-4 Torr to 1000 atm based on dual channel Rice-Ramsperger-Kassel-Marcus (RRKM) calculations with the potential energy surface evaluated at the G2M and CCSD(T) levels. The rate constant calculated by variational RRKM theory agrees reasonably with experimental data.
Kinetics and mechanism of the NCN + NO2 reaction studied by experiment and theory
Yang, Tsung-Ju,Wang, Niann S.,Lee,Xu,Lin
, p. 10185 - 10192 (2008)
The rate constant for the NCN + NO2 reaction has been measured by a laser photolysis/laser-induced fluorescence technique in the temperature range of 260-296 K at pressures between 100 and 500 Torr with He and N2 as buffer gases. The NCN radical was produced from the photolysis of NCN 3 at 193 nm and monitored by laser-induced fluorescence with a dye laser at 329.01 nm. The rate constant was found to increase with pressure but decrease with temperature, indicating that the reaction occurs via a long-lived intermediate stabilized by collisions with buffer gas. The reaction mechanism and rate constant are also theoretically predicted for the temperature range of 200-2000 K and the He and N2 pressure range of 10-4 Torr to 1000 atm based on dual-channel Rice-Ramsperger-Kassel-Marcus (RRKM) theory with the potential energy surface evaluated at the G2M//B3LYP/6-311+G(d) level. In the low-temperature range (2). At high temperature, the direct O-abstraction reaction with a barrier of 9.8 kcal/mol becomes the dominant channel. The rate constant calculated by RRKM theory agrees reasonably well with experimental data.
Selective Synthesis and Characterization of the Highly Energetic Materials 1-Hydroxy-5H-tetrazole (CHN4O), its Anion 1-Oxido-5H-tetrazolate (CN4O?) and Bis(1-hydroxytetrazol-5-yl)triazene
Klap?tke, Thomas M.,Kofen, Moritz,Schmidt, Laszlo,Stierstorfer, J?rg,Wurzenberger, Maximilian H. H.
, p. 3001 - 3012 (2021)
For the first time, an adequate selective synthesis, circumventing the formation of 2-hydroxy-5H-tetrazole, of 1-hydroxy-5H-tetrazole (HTO), as well as the synthesis of bis(1-hydroxytetrazol-5-yl)triazene (H3T) are reported. Several salts thereof were synthesized and characterized which resulted in the formation of new primary and secondary explosives containing the 1-oxidotetrazolate unit. Molecular structures are characterized by single-crystal X-ray diffraction, 1H and 13C NMR, IR, and elemental analysis. Calculation of the detonation performance using the Explo5 code confirmed the energetic properties of 1-hydroxy-5H-tetrazole. The detonation properties can be adjusted to the requirements for those of a secondary explosive by forming the hydroxylammonium (6) or hydrazinium (7) salts, or to meet the requirements of a primary explosive by forming the silver salt 4, which shows a fast DDT on contact with a flame. The sensitivities of all compounds towards external stimuli such as impact, friction, and electrostatic discharge were measured.
Nitroimino-tetrazolates and oxy-nitroimino-tetrazolates
Joo, Young-Hyuk,Shreeve, Jean'Ne M.
, p. 15081 - 15090 (2010)
Highly energetic 1,1′-ethylenebis(oxy)bis(5-nitroimino-tetrazolate) salts were obtained by reacting equimolar quantities of the acidic 1,1′-ethylenebis(oxy)bis(5-nitroimino-tetrazole) and energetic bases in aqueous solution. Addtionally, metathesis of silver 1,1′-ethylenebis(oxy) bis(5-nitroimino-tetrazolate) with diaminoguanidinium chloride or triaminoguanidinium chloride gave the corresponding oxy-nitroimino-tetrazolate salt. These salts were fully characterized using IR and multinuclear NMR spectroscopy, elemental analysis, and differential scanning calorimetry (DSC), and, in some cases, 2?2H2O, 8?2H2O, 10, 13?2H2O and 14, with single crystal X-ray structuring. The heats of formation for all compounds were calculated with Gaussian 03 and then combined with measured densities to determine detonation pressures (P) and velocities (D) of the energetic materials (Cheetah 5.0). The impact sensitivities of all salts were found to be less than those of the parent compounds. The physical and detonation properties of these oxy-nitroimino- tetrazolate salts are comparable to the analogous newly prepared diaminoguanidinium and triaminoguanidinium 1,1′-ethylenebis(5-nitroimino- tetrazolate)s.
Dissociation of cyanogen azide: An alternative route to synthesis of carbon nitride
Benard,Linnen,Harker, Alan,Michels,Addison,Ondercin
, p. 6010 - 6019 (1998)
Solid films composed principally of carbon and nitrogen were grown on a variety of substrates at ambient temperature in a flow-tube reactor by upstream mixing of cyanogen azide, cyanogen, or cyanogen halides with active nitrogen obtained from an electrical discharge. Ab initio calculations and dependence of deposition rates on both choice of donor and N atom production suggests that NCN radicals are a critical growth species. The films obtained are electrically insulating with a refractive index of 2.3 at visible wavelength and are optically transparent from 550 nm out to at least 14 ??m with the exception of two broad absorption bands centered at 1550 and 3250 cm-1, the latter band growing in upon exposure of the film to atmospheric moisture. Film analysis by X-ray photoelectron spectroscopy revealed comparable concentrations of both carbon-to-nitrogen bonds (with approximate C3N4 stoichiometry) and diamond-like carbon-to-carbon bonds as well as minority bonding of carbon to impurities.
Energetic salts based on 1-methoxy-5-nitroiminotetrazole
Joo, Young-Hyuk,Chung, Jin Hyuk,Cho, Soo Gyeong,Goh, Eun Mee
, p. 1180 - 1188 (2013)
Eight new energetic salts based on 1-methoxy-5-nitroiminotetrazole, which was obtained by nitration of 1-methoxy-5-aminotetrazole, were synthesized. Guanidinium (5), aminoguanidinium (6), diaminoguanidinium (7), triaminoguanidinium (8), carbohydrazidinium (9), 3-amino-1,2,4-triazolium (10), 4-amino-1,2,4-triazolium (11), and 3,5-diamino-1,2,4-triazolium (12) salts were characterized by vibrational spectroscopy (IR, Raman), multinuclear spectroscopy (1H, 13C, 15N), elemental analysis, and single crystal X-ray diffraction analysis. Salts 5·1/3H2O and 7-9 crystallize in the triclinic space group P1, whereas compounds 6 and 10 crystallize in the monoclinic space groups C2/c and P2(1)/n, respectively. Compound 11 is in orthorhombic group P2(1)2(1)2(1). In addition, the heats of formation (ΔHf), and detonation properties (pressure and velocity) were calculated using Gaussian 03 and EXPLO5 programs, respectively. Thermal stabilities were obtained by DSC measurements and the sensitivities toward impact and friction were determined by BAM methods.
Thermal decomposition of NCN3 as a high-temperature NCN radical source: Singlet-triplet relaxation and absorption cross section of NCN( 3Σ)
Dammeier,Friedrichs
, p. 12963 - 12971 (2010)
The potential of the thermal decomposition of cyanogen azide (NCN 3) as a high-temperature cyanonitrene (NCN) source has been investigated in shock tube experiments. Electronic ground-state NCN( 3Σ) radicals have been detected by narrow-bandwidth laser absorption at overlapping transitions belonging to the Q1 branch of the vibronic 3Σ+-3Π subband of the vibrationally hot A3Πu(010)-X 3Σg-(010) system at ν = 30383.11 cm-1 (329.1302 nm). High-temperature absorption cross sections σ have been directly measured at total pressures of 0.2-2.5 bar, log[σ/(cm2 mol-1)] = 8.9-8.3 × 10-4 × T/K (±25%, 750 3Σ) formation is limited by a slow electronic relaxation of the initially formed excited NCN(1Δ) radical rather than thermal decomposition of NCN3. Measured temperature-dependent collision-induced intersystem crossing (CIISC) rate constants are best represented by kCIISC/(cm3 mol-1 s -1) = (1.3 ± 0.5) × 1011 exp[-(21 ± 4) kJ/mol/RT] (740 3 is an ideal precursor for NCN kinetic experiments behind shock waves.
Imino-bridged N-rich energetic materials: C4H3N17and their derivatives assembled from the powerful combination of four tetrazoles
Dong, Zhen,Li, Haiyan,Liu, Yaxin,Liu, Yifei,Yang, Rui,Ye, Zhiwen
, p. 5377 - 5384 (2021)
This study reports the synthesis of a series of novel imino-bridged N-rich energetic compounds, namely C4H3N17(N%: 82.4) and their derivatives, which were formed by four tetrazole (CN4) moieties. C4N173?could be acidified by different concentrations of HCl and N-rich anions such as C4H2N17?and the neutral compound3(C4H3N17) could be obtained. The new compounds all exhibit good energetic performance (D: 8023-9668 m s?1; Td: 169-277 °C; IS > 25 J; FS > 252 N). Remarkably, the ammonia oxide adduct compound8(C4H15N21O4) was exceedingly powerful (D: 9668 m s?1) similar to CL-20 (9706 m s?1) and showed good stability (Td: 168 °C; IS > 40 J; FS > 360 N). Moreover, compound11(C4H8NaN19) exhibits not only the thermal stability and high density of metallic salts but also the mechanical stability of nonmetallic salts, which provides an important strategy for the design and synthesis of energetic materials. Among them, compounds3,4, and6-11were characterizedviasingle-crystal diffraction to further confirm their exact molecular structure and arrangement.
3,4-Dinitro-1-(1H-tetrazol-5-yl)-1H-pyrazol-5-amine (HANTP) and its salts: primary and secondary explosives
Fu, Wei,Zhao, Baojing,Zhang, Man,Li, Chuan,Gao, Huiqi,Zhang, Jun,Zhou, Zhiming
, p. 5044 - 5054 (2017/03/15)
The combination of superior energetic structural fragments is a feasible route to design new energetic materials. In this work, selected metal and nitrogen-rich salts based on 3,4-dinitro-1-(1H-tetrazol-5-yl)-1H-pyrazol-5-amine (HANTP) are prepared and characterized by 1H/13C NMR, IR spectroscopy, and elemental analysis. The crystal structures of neutral HANTP (2), and its potassium (4), sodium (5), ammonium (6), and guanidinium (9) salts are determined by single-crystal X-ray diffraction, and their properties (density, thermal stability, and sensitivity towards impact and friction) are investigated. The detonation properties are evaluated by the EXPLO5 (v6.01) program using the measured density and calculated heat of formation (Gaussian 03). All compounds exhibit thermal stabilities with decomposition temperatures ranging from 171 to 270 °C, high densities (1.61-2.92 g cm?3), and high positive heats of formation (630.4-1275.2 kJ mol?1). The inorganic salts (4 and 5) assume particular structures (two-dimensional and one-dimensional metal-organic frameworks, respectively). Suitable impact and friction sensitivities and being free of toxic metals place these compounds within the green primary explosives group and several of the new organic salts exhibit detonation and other properties that compete with, or exceed the performance of those of HMX.
Connecting energetic nitropyrazole and aminotetrazole moieties with: N, N ′-ethylene bridges: A promising approach for fine tuning energetic properties
Kumar, Dheeraj,He, Chunlin,Mitchell, Lauren A.,Parrish, Damon A.,Shreeve, Jean'Ne M.
, p. 9220 - 9228 (2016/07/06)
A new approach for fine tuning the properties of energetic compounds through bonding of energetic pyrazoles with tetrazole moieties by means of N,N′-ethylene bridges is described. Reactions of various pyrazole derivatives with 2-haloethylamines, followed by reaction with cyanogen azide resulted in the formation of compounds having ethylene-bridged 5-aminotetrazole and nitropyrazole. Further reactions on this basic framework resulted in various energetic compounds having mono, di or tri nitro-substituted pyrazole moieties, and an amino or nitroimino-substituted tetrazole ring. All the compounds were thoroughly characterized by IR, and NMR [1H, 13C{1H}, 15N] spectra, elemental analysis, and differential scanning calorimetry (DSC). Some of them were also structurally characterized with single-crystal X-ray diffraction studies. Heats of formation and detonation performance for all the energetic compounds were calculated using Gaussian 03 and EXPLO5 v6.01 programs, respectively. Initial studies showed that the properties of energetic compounds can indeed be fine-tuned by careful selection of the number and nature of energetic groups on the pyrazole and tetrazole rings.
