Two nitrogen-rich Ni(ii) coordination compounds based on 5,5′-azotetrazole: synthesis, characterization and effect on thermal decomposition for RDX, HMX and AP

Abstract

Two novel multiligand coordination complexes of Ni(II), [Ni(en)₃]AZT·THF (1) (en = ethylene diamine, THF = tetrahydrofuran) and [Ni(AZT)(pn)₂]_n (2) (pn = propylene diamine), were prepared from the corresponding Ni salts and have been structurally characterized by elemental analysis, Fourier transform infrared spectroscopy and single crystal X-ray diffraction. The results show that both 1 and 2 crystallize in the triclinic space group P. 1 presents a zero-dimensional unit, while 2 exhibits a one-dimensional zigzag chain. Under nitrogen, the thermal decomposition process and the kinetic parameters of the two complexes were studied by TG-DTG and DSC technologies. The non-isothermal kinetic parameters were calculated by Kissinger's and Ozawa–Doyle's methods. Furthermore, the compounds were explored as additives to promote the thermal decomposition of cyclotrimethylene trinitramine (RDX), cyclotetramethylene tetranitramine (HMX) and ammonium perchlorate (AP) by differential scanning calorimetry.