Zn(Met)Ac_2·H_2O固态配合物的制备及标准生成焓

Preparation and Standard Enthalpy of Formation of Zn(Met)Ac_2·H_2O

在水 丙酮混合溶剂中合成了Zn(Met)Ac2 ·H2 O固态配合物 ,通过化学分析、元素分析、IR、DSC和TG DTG对其组成、结构及热稳定性进行了表征。得出其脱水过程和分解过程的焓变分别为 15 30J/ g和35 7 80J/ g。用转动弹热量计测得其恒容燃烧能ΔcE为 (- 6 4 72 11± 2 2 0 )kJ/mol,计算得其标准燃烧焓ΔcH0m 和标准生成焓ΔfH0m 分别为 (- 6 4 75 2 1± 2 2 0 )kJ/mol和 (- 4 2 9 0 4± 2 5 9)kJ/mol。

The complex of methionine with ZnAc 2·2H 2O was prepared in a water-acetone mixture. Its composition was identified as Zn(Met)Ac 2·H 2O by chemical and elemental analyses. The structure and thermal stability of the complex were investigated by IR, DSC and TG-DTG, its enthalpies in dehydrolysis and decomposition courses were obtained as 15.30 J/g and 357.80 J/g, respectively. The constant volume combustion energy of the complex, Δ cE, was determined as (-6 472.11±2.20) kJ/mol by a precise rotating-bomb calorimeter at 298.15 K, its standard enthalpy of combustion, Δ cH θ m, and standard enthalpy of formation, Δ fH θ m, were calculated as (-6 475.21±2.20) kJ/mol and (-429.04±2.59) kJ/mol, respectively.