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

Abstract

An energetic complex, [Cd₂(μ-Cl)₄Cl₂(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 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 M⁻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.

Graphical abstract

A new 1D Cd complex based on 3,4-diamino-1,2,4-triazole was synthesized and structurally characterized. Its thermal stability, non-isothermal kinetics analysis, and theoretical calculation were studied, and energy of combustion was also measured.

Keywords:

• Energetic complex
• 3,4-Diamino-1,2,4-triazole ligand
• Molecular structure
• Thermal decomposition
• Quantum chemical calculation

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The work was financially supported from the National Natural Science Foundation of China [grant number 10776002] and the project of State Key Laboratory of Science and Technology [grant number ZDKT12-03], [grant number YBKT16-04].