Crystal Structure and Thermal Decomposition Mechanism of [K（DNP）（H2O）0.5]n
摘要
The new coordination polymer, [K(DNP)(H2O)0.5]n(DNP= 2,4-dinitrophenol) was prepared by the reaction of 2,4-dinitrophenol with potassium hydroxide. The molecular structure was determined by X-ray single-crystal diffraction analysis, FT-IR techniques, and elemental analysis. The crystal is monoclinic, space group C(2)/c with the empirical formula of C6H4N2O5.5K, Mr=231.21. The unit cell parameters are as follows: α=2.0789(3)nm, b=1.2311(2)nm, c=0.7203(1)nm, β= 109.611(151)°, V=1.7366(4) nm^3, Z=4, Dc= 1.769g/cm^3, F(000)=936,μ(Mo Kα)=0.617mm^-1. The potassium ions coordinate with all the oxygen atoms of phenolic hydroxyl group and nitro-group of different 2,4-dinitrophenol (DNP) ligands with high coordination number, and form a good cross-linked three-dimensional net structure of which makes the complex with good stabilities. The thermal decomposition of [K(DNP)(H2O)0.5]n has only an intense exothermic process in the temperature range of 338-343℃ corresponding to a mass loss of 75.02%. The final decomposition residue is potassium isocyanide.