Preparation, crystal structure, thermal decomposition mechanism and thermodynamic properties of [Co(H2O)6](NTO)2·2H2O

The single crystal of cobalt compound of 3-nitro-1,2,4-triazol-5-one (NTO) ([Co(H2O)6](NTO)2·2H2O) was prepared and the crystal structure has been determined by a four-circle X-ray diffractometer. The compound is monoclinic with space group Cc and unit cell parameters of <F>a=2.3163</F> (2) nm, <F>b=0.6451</F> (1) nm, <F>c=1.4123</F> (1) nm, <F>β=123.96</F> (1)°, <F>V=1.7504</F> (3) nm3 and <F>Z=4</F>. Based on the thermal analysis, the thermal decomposition mechanism of [Co(H2O)6](NTO)2·2H2O has been derived. From measurements of the enthalpy of solution in water at 298.15 K, the standard enthalpy of formation, lattice enthalpy and lattice energy have been determined as <F>-(2594.7±4.5)</F>, -2753.19, and -2718.19 kJ mol-1, respectively. [Copyright &y& Elsevier]