CAJ | 학술논문

合成了稀土氯化钬丙氨酸配合物, [Ho2(Ala)4(H2O)8]Cl6,的晶体 .用绝热量热法测定了其在 78～ 363 K温区的热容 .在 214～ 255 K温区发现一固-固相变,相变峰温、相变焓和相变熵分别为 235.09 K, 3.017 kJ@ mol- 1和 12.83 J@ K- 1@ mol- 1.用最小二乘法将实验热容值拟合成热容随温度变化的多项式方程 ,利用此方程式和热力学函数关系 ,计算出以 298.15 K为参考温度的热力学函数值 .在 40～ 800 ℃温区,用热重分析和差示扫描量热法研究了该配合物的热稳定性,观察到 [Ho2(Ala)4(H2O)8]Cl6分两步分解,第一步从 80 ℃开始, 179 ℃结束;第二步从 242 ℃开始, 479 ℃结束 .从热分析结果推测出该配合物可能的热分解机理 .
합성료희토록화화병안산배합물, [Ho2(Ala)4(H2O)8]Cl6,적정체 .용절열량열법측정료기재 78～ 363 K온구적열용 .재 214～ 255 K온구발현일고-고상변,상변봉온、상변함화상변적분별위 235.09 K, 3.017 kJ@ mol- 1화 12.83 J@ K- 1@ mol- 1.용최소이승법장실험열용치의합성열용수온도변화적다항식방정 ,이용차방정식화열역학함수관계 ,계산출이 298.15 K위삼고온도적열역학함수치 .재 40～ 800 ℃온구,용열중분석화차시소묘량열법연구료해배합물적열은정성,관찰도 [Ho2(Ala)4(H2O)8]Cl6분량보분해,제일보종 80 ℃개시, 179 ℃결속;제이보종 242 ℃개시, 479 ℃결속 .종열분석결과추측출해배합물가능적열분해궤리 .
The crystalline complex of holmium chloride with alanine,[Ho2(Ala)4(H2O)8]Cl6,was synthesized.Heat capacities of [Ho2(Ala)4(H2O)8]Cl6 were measured by adiabatic calorimetry over the temperature range from 78 to 363 K.A solid-solid phase transition was found between 214 K and 255 K with the peak temperature of 235.09 K.The enthalpy and entropy of the transition were determined to be 3.017 kJ@ mol- 1 and 12.83 J@ K- 1@ mol- 1,respectively.The molar heat capacities were presented by a fitted polynomial as a function of reduced temperature.The thermodynamic functions relative to the reference temperature 298.15 K were calculated based on the heat capacity data.Thermal stability of the complex was studied by thermogravimetry (TG) and differential scanning calorimetry (DSC) over the temperature range from 40 to 800 ℃ .From the DTG curves,two peaks were observed in the process of the thermal decompositions for the complex.The first mass-loss peak started from 80 ℃ and ended at 179 ℃ ,and the second mass-loss peak started from 242 ℃ and ended at 479 ℃ .A possible mechanism of the thermal decomposition was presented.