Preparation, crystal structure and thermal decomposition mechanism of [K(HTNR)(H₂O)]_n

The new coordination polymer of potassium 2,4,6-trinitroresorcinate, [K(HTNR) (H₂O)]_n, was prepared by reacting 2,4,6-trinitroresorcinol with potassium hydroxide in alcohol solution. Its crystal structure was determined by X-ray single crystal diffraction analysis. The crystalline belongs to monoclinic with space group P2₁/c. Its unit cell parameters are as follows: a = 0.7888(1) nm, b = 1.3800(2) nm, c = 0.9520(1) nm, β = 8.91(1)°, V = 1.0238 (2) nm³, D _c = 1.954 g/cm³, Z = 4, F(000) = 608, μ(Mo Kα) = 0.575 mm^-1. The thermal decomposition mechanism of the complex was studied by using differential scanning calorimetry (DSC), thermogravimetry- derivative thermogravimetry (TG-DTG) and FT-IR techniques. At the linear heated rate the thermal decomposition of the complex contained two overlapped weak endothermic and two intense exothermic processes. There are KNCO and RCOOK at 271. 9 °C, and KNC at 357.1 °C in the residue according to FT-IR analysis.