[Li(NTO)(H2O)2] was prepared by mixing the aqueous solution of 3-nitro-1, 2, 4-triazol-5-one (NTO) and lithium hydroxide. The crystal structure of [Li(NTO)(H2O)2] was determined by single crystal diffraction analysis. The crystal is monoclinic, space group P21/n with crystal parameters of α=0.742 0(2)nm, b=0.344 9(1)nm, c=2.490 6(3)nm, β=94.89(1)α, Z=4, Dc=1.799g. cm 3, V=0.635nm3, μ=l.591cm-1, F(000)=392. The finaIR is 0.051. TheMNDOMOcalculation shows that the coordinate bonds of title compound possess certain extent of covalent character. 02 atom of NTO anion is bonded to Li atom; the nitro group will be lost first when NTO is decomposed.

The single crystal of lead salt of 3-nitro- 1, 2, 4-triazol-5-one (NTO), [Pb(NTO)2.H20] was prepared and its structure was determined by a four-circle X-ray diffractometer. The crystal is monoclinic, its space group is P21/n with crystal parameters of a=0.7262(1) rim, b=1.2129(2)nm, c=1.2268(3)nm, [3=90.38(2)o, V=1.0806(2)nm3, Z=4, Dc=2.97gcm-3, p.=157.83cm-1, F(000)=888. The final R is 0.027. By using SCF-PM3-MO method we obtained optimized geometry for [Pb(NTO)2.H20] and particularly positions for hydrogen atoms. Through the analyses of MO levels and bond orders it is found that Pb atom bond to ligands mainly with its 6p, and 6py AOs. The thermal decomposition experiments are elucidated when [Pb(NTO)z.H20] is heated, ligand water is dissociated first and NO2 group has priority of leaving. Based on the thermal analysis, the thermal decomposition mechanism of [Pb(NTO)2.H20] has been derived. The lattice enthalpy and its lattice energy were also estimated.

H[Pr(NTO)4(H2O)4]-2H2O was prepared by mixing the aqueous solution of lithium 3-nitro-1,2,4-triazol-5-onate and the dilute nitric acid solution of Pr6O11. The single crystal structure has been determined by a four-circle X-ray diffractometer. The crystal is triclinic, space group P1 with crystal parameters of a=1.0463(10)nm, b=1.0484(10)nm, c=1.1474(10)nm,α=99.10(10)0, β=96. 96(10)0, r=97.65(10)0, V=1.2186(2)nm3, Z-2, Dc-2.088g-cmÿ3, u=21.17 cmÿ1, F(0 0 0)540. The final R is 0.0206. Based on the thermal analysis, the thermal decomposition mechanism of H[Pr(NTO)4(H2O)4]-2H2O has been derived. From measurements of the enthalpy of solution in water of H[Pr(NTO)4(H2O)4]-2H2O at 298.15 K, the standard enthalpy of formation, lattice energy and lattice enthalpy have been determined as ÿ(2884.1 8.9), ÿ5443.25 and ÿ5473.25 kJ molÿ1, respectively.

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 a=2.3163 (2)nm, b=0.6451 (1) nm, c=1.4123 (1)nm, β=123.96 (1)◦, V=1.7504 (3)nm3 and Z=4. 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 −(2594.7±4.5), −2753.19, and −2718.19 kJ mol−1, respectively.

通过3-硝基-1，2，4-三唑-5-酮（NT0）与氢氧化钾水溶液反应，制备了标题配合物，并用TG，元素分析，红外光谱分析对它进行了表征．其结构用单晶分析法测定，所得晶体学参数为α=0.6408（1），6=0.8218（1），c=1.2626（1）nm，β=100．63°（1），V=0.6535（1）nm3，Z=4，Dc=1.892g•cn-3，μ=0.785mm-1，F（000）=376；晶体属单斜晶系，空间群为P21/n，最终偏离因子R为0.0246用EHMo计算表明，标题化合物主要是靠静电引力形成的配合物，中心原子K与H2O的配位较K与Nm环的结合弱，预示热解优先脱水。