以五水硫酸铜、甘氨酰甘氨酸(Gly-Gly)、咪唑(Im)为原料,制备了甘氨酰甘氨酸咪唑铜配合物,通过X射线单晶衍射测定了配合物的结构。该晶体属单斜晶系,P21/n空间群,a=1.0213(6)nm,b=0.7023(4)nm,c=1.5911(9)nm,β=102.393(9)°,V=1.1147(11)nm3,Z=4。用溶解量热法分别测定了CuSO4·5H2O(s)+Gly-Gly(s)+Na2SO4(s)、Im(s)和[Cu(Gly-Gly)(Im)]·2H2O(s)、NaHSO4·H2O(s)在2mol/L HCl中的溶解焓。根据Hess定律设计了一个热化学循环,计算得到CuSO4·5H2O(s)+Gly-Gly(s)+Im(s)+Na2SO4(s)=[Cu(Gly-Gly)(Im)]·2H2O(s)+2NaHSO4·H2O(s)+H2O(l)的反应焓ΔrHmθ (298.15K)=(36.7634±1.1325)kJ/mol,进而求出[Cu(Gly-Gly)(Im)]·2H2O(s)的标准生成焓ΔrHmθ{[Cu(Gly-Gly)(Im)]·2H2O(s), 298.15K}=(-1770.3±1.4)kJ/mol。
Complex [Cu(Gly-Gly)(Im)]·2H2O(s) was prepared by mixing the solution of copper sulfate pentahydrate, glycylglycine and imidazole. The crystal structure of [Cu(Gly-Gly)(Im)]·2H2O was determined by X-Ray single crystal diffraction. The crystal belongs monoclinic with space group P21/n and unit-cell parameters are a=1.0213(6)nm, b=0.7023(4)nm, c=1.5911(9)nm, β=102.393(9)°, V=1.1147(11)nm3, and Z=4, respectively. The dissolution enthalpies of CuSO4·5H2O(s)+Gly-Gly(s)+Na2SO4(s), Im(s) and [Cu(Gly-Gly) (Im)]·2H2O(s), 2NaHSO4·H2O(s) have been determined in 2mol/L HCl solution by the classical solution calorimetry. According to Hess law, a thermochemical cycle is designed. By calculation, the reaction enthalpy of CuSO4·5H2O(s)+Gly-Gly(s)+Im(s)+Na2SO4(s)=[Cu(Gly-Gly)(Im)]·2H2O(s)+2Na·HSO4·H2O(s)+H2O(l) is calculated, ΔrHmθ(298.15K)=(36.763,4±1.132,5)kJ/mol, and furthermore the standard formation enthalpy of [Cu(Gly-Gly)(Im)]·2H2O(s) has also been calculated, ΔrHmθ{[Cu(Gly-Gly)(Im)]·2H2O(s), 298.15K}=(-1,770.3±1.4)kJ/mol.