Synthesis, structure and thermokinetic studies on perchlorate salts of metal complexes containing a formamidine-type ligand

Holló, Berta Barta; Jašo, Vladislav; Leovac, Vukadin M.; Divjaković, Vladimir; Kovács, Attila; Szécsényi, Katalin Mészáros

doi:10.1080/00958972.2012.761338

Cited by 5 publications

(2 citation statements)

References 44 publications

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“…T p is the temperature (K) at which the first exothermic peak occurs in the DSC curve; A is the pre-exponential factor [s -1 ]; E a is the apparent activation energy [kJ·mol -1 ]; R is the gas constant Comparison of the value of the average activation energy of 166.5 kJ·mol -1 for 1 with literature data for energetic cobalt(II) complex [46] shows that the values are analogous.…”

Section: Non-isothermal Kinetics Analysismentioning

confidence: 99%

A 1D cadmium complex with 3,4-diamino-1,2,4-triazole as ligand: synthesis, molecular structure, characterization, and theoretical studies

Jin

Yin

et al. 2015

Journal of Coordination Chemistry

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2015): A 1D cadmium complex with 3,4-diamino-1,2,4-triazole as ligand: Synthesis, molecular structure, characterization, and theoretical studies, Journal of Coordination Chemistry, An energetic complex, [Cd 2 (μ-Cl) 4 Cl 2 (DATr) 2 ] n (1) (DATr = 3,4-diamino-1,2,4-triazole), was synthesized from DATr·HCl and cadmium(II) chloride. The product was characterized by Fourier transform-infrared spectroscopy (FT-IR) analysis, elemental analysis, X-ray diffraction analysis, and differential scanning calorimeter (DSC) analysis. The central cadmium(II) ions in 1 are six-coordinate twisted octahedral structures, which are made up of 1D chains linked by bridging chlorides. The results of the DSC analysis suggest the temperature of decomposition to be above 503.15 K. Furthermore, the kinetic properties of decomposition are studied by Kissinger's and Ozawa-Doyle's methods, and the calculated average activation is 166.5 kJ·mol -1 , which means the complex is stable under normal conditions. In addition, the energy of combustion was measured by oxygen bomb calorimetry. The critical temperature of thermal explosion and parameters of thermodynamics of 1 were calculated. The periodic structure of 1 has been calculated based on the density functional theory. The theoretical results explain the electronic structure and thermal dynamic properties.

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Section: Non-isothermal Kinetics Analysismentioning

confidence: 99%

A 1D cadmium complex with 3,4-diamino-1,2,4-triazole as ligand: synthesis, molecular structure, characterization, and theoretical studies

Jin

Yin

et al. 2015

Journal of Coordination Chemistry

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“…Energetic materials include explosives, propellants and pyrotechnics that are used for a variety of military purposes and civilian applications . Tetrazoles are an important core of aza‐containing heterocycles because of the practical and theoretical significance and the diversity of their characteristics . Aminotetrazoles have the highest content of nitrogen among all organic substances, thereinto, 84.0% for the compound 1,5‐diaminotetrazole (DAT).…”

Section: Introductionmentioning

confidence: 99%

Theoretical kinetic study on the decomposition of 1,5-diaminotetrazole

Zhang

Liu

et al. 2015

J. Phys. Org. Chem.

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1,5-Daminotetrazole (DAT) is of much interest because of the practical significance and the diversity of characteristics. The study on the decomposition pathway and the kinetics of DAT has been performed based on the quantum chemistry theory. The minimum energy path (MEP) calculation has shown that NH 2 N 3 and NH 2 CN are the initially detected products of DAT. And the structures of reactant, products and transition state were optimized with MP2 methods using 6-311G** basis sets, and the energies were refined using CCSD(T)/6-311G** levels of theory. The calculated rate constants were obtained using the conventional transition-state theory (TST) and the canonical variational transition-state theory (CVT) methods. The calculation results indicated that the energy barrier of decomposition reaction is 47.98 kcal mol À1 and the variational effect is small. In addition, the rate constants and the Arrhenius experience formula of DAT decomposition have been obtained between 200 and 2500 K temperature regions. The fitted three-parameter expressions calculated using the TST and CVT methods are k T

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Theoretical study on the tautomerization of 1,5-diaminotetrazole (DAT)

Zhang

Liu

et al. 2014

J Mol Model

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The tautomerization pathways and kinetics of 1,5-diaminotetrazole (DAT) have been investigated by means of second-order Møller-Plesset perturbation theory (MP2) and coupled-cluster theory, with single and double excitations including perturbative corrections for triple excitations (CCSD(T)). Five possible tautomers, namely 4-hydro-1-amino-5-imino-tetrazole (a), 2,5-diamino-tetrazole (b), 1,5-diamino-tetrazole (c), 2-hydro-1-imino-5-amino-tetrazole (d), and 2,4-dihydro-1,5-diimino-tetrazole (e) were identified. The structures of the reactants, transition states, and products along with the tautomerism pathways were optimized by the MP2 method using the 6-311G** basis set, and the energies were refined using CCSD(T)/6-311G**. The minimum-energy path (MEP) information for DAT was obtained at the CCSD(T)/6-311G**//MP2/6-311G** level of theory. Therein, reaction 2 (c → b) is an amino-shift reaction, while reaction 1 (c → a), reaction 3 (c → d), reaction 4 (a → e), and reaction 5 (d → e) are reactions of hydrogen-shift tautomerization. The calculated results show that 2,5-diaminotetrazole (b) with the minimum energy (taking c as a standard) among five tautomers, is the energetically preferred tautomer of DAT in the gas phase. In addition, the energy barrier of reaction 2 is 71.65 kcal · mol(-1) in the gas phase, while reaction 1 takes place more easily with an activation barrier of 61.53 kcal · mol(-1) also as compared to 63.71 kcal · mol(-1) in reaction 3. Moreover, the tautomerization of reaction 4 requires the largest energy barrier of 83.29 kcal · mol(-1), which is obviously bigger than reaction 5 with a value of 73.78 kcal · mol(-1). Thus, the hydrogen-shift of c to a is the easiest transformation, while the tautomerization of a to e is the hardest one. Again, the rate constants of tautomerization have been obtained by TST, TST/Eckart, CVT, CVT/SCT, and CVT/ZCT methods in the range 200-2500 K, and analysis indicated that variational effects are small over the whole temperature range, while tunneling effects are significant in the lower temperature range.

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Synthesis, structure and thermokinetic studies on perchlorate salts of metal complexes containing a formamidine-type ligand

Cited by 5 publications

References 44 publications

A 1D cadmium complex with 3,4-diamino-1,2,4-triazole as ligand: synthesis, molecular structure, characterization, and theoretical studies

A 1D cadmium complex with 3,4-diamino-1,2,4-triazole as ligand: synthesis, molecular structure, characterization, and theoretical studies

Theoretical kinetic study on the decomposition of 1,5-diaminotetrazole

Theoretical study on the tautomerization of 1,5-diaminotetrazole (DAT)

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