摘要
合成表征了氯化钆与L 酪氨酸和甘氨酸形成的三元固态配合物Gd(Tyr) (Gly) 3 Cl3 ·3H2 O .用具有恒温环境的溶解 -反应热量计 ,测定了配位反应GdCl3 ·6H2 O (s) +Tyr (s) +3Gly (s) =Gd(Tyr) (Gly) 3 Cl3 ·3H2 O (s) +3H2 O (l)在 2 98.15K时的反应焓为 ( 9.45 1± 0 .468)kJ·mol-1 .计算得配合物Gd(Tyr) (Gly) 3 Cl3 ·3H2 O (s)在 2 98.15K时的标准摩尔生成焓为ΔfH m =-( 4 2 69.7± 2 .3 )kJ·mol-1 .并用热分析手段对配合物进行了非等温热分解动力学研究 ,推断配合物第二步热分解反应机理为二级化学反应 ,其动力学方程为 :dα/dT =(A/β)exp( -E/RT) ( 1-α) 2 ,求得分解反应的表观活化能为E =2 15 .17kJ·mol-1 ,指前因子为 10 1 8.71 s-1 .
The ternary solid state complex of gadolinium chloride with L tyrosine and glycine, Gd(Tyr)(Gly) 3Cl 3·3H 2O, was synthesized and characterized. Using a solution reaction isoperibol calorimeter, the molar enthalpy of reaction for the following reaction: GdCl 3·6H 2O (s)+Tyr (s)+3Gly (s)=Gd(Tyr)(Gly) 3Cl 3·3H 2O (s)+3H 2O (l), was determined to be (9.451±0.468) kJ·mol -1 at 298.15 K. From the above molar enthalpy of reaction and other auxiliary thermodynamic quantities, the standard molar enthalpy of formation of the titled complex at 298.15 K was derived as -(4269.7±2.3) kJ·mol -1. The kinetics of thermal decomposition of the complex was studied by thermal analysis technique under non isothermal condition. The possible reaction mechanism was suggested to be a second order chemical reaction. The kinetic equation may be expressed as: dα/dT=(A/β)exp(-E/RT)(1-α) 2. The apparent activation energy and pre exponential factor of the reaction were 215.17 kJ·mol -1 and 10 18.71 s -1, respectively.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2004年第4期386-390,共5页
Acta Chimica Sinica
基金
教育部高校优秀青年教师教学科研奖励计划资助项目 (2 0 0 1 )
