Preparation, crystal structure and thermal decomposition mechanisms of {[Cd(NTO)₂(CHZ)] · 2H₂O}_n

The coordination compound of {[Cd(NTO)₂(CHZ)] · 2H ₂O}_n was prepared by the reaction of cadmium salt of 3-nitro-1, 2, 4-triazol-5-one (NTO) with carbohydrazide (CHZ) in solution. The crystal structure of {[Cd(NTO)₂ (CHZ)] · 2H₂O} _n was determined by X-ray diffraction analysis. Thermal decomposition mechanism of the compound was studied using TG-DTG, DSC and IR techniques. The crystals belong to orthorhombic with space group Pbca. The unit cell parameters are as follows: a = 0.8623(1)nm, b = 1.8259(4)nm, c = 1.9997(3)nm, Z = 8, R ₁ = 0.0517, wR₂ = 0.0655. The coordination number of the cadmium cation is six and the Cd²⁺ ion shows a distorted octahedral geometry. The NTO serves as a bridging bidentate ligand, coordinated to two cadmium cations with its carbonyl oxygen atom and the nitrogen atom of 4-position. The CHZ serves as a tri-dentate ligand, coordinated to a cadmium cation with its carbonyl oxygen atom and one of the two nitrogen atoms. At the same time, it is coordinated to the second cadmium cation using other end nitrogen atom. The results demonstrate that the three-dimensional infinite super-molecular network is constructed.