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合成了四氯合镉酸正十一烷铵配合物(C11H23NH3)2CdCl4(s)[简写:C11Cd(s)].用X射线单晶衍射技术、化学分析和元素分析确定其晶体结构和化学组成.利用其晶体学数据计算出晶格能为:UPOT=908.18 kJ·mol-1.利用精密自动绝热热量计测定了它在78～395 K温区的低温热容,结果表明,该配合物在此温区出现两次连续的固-固相转变,计算出两次相变的峰温、摩尔焓及摩尔熵分别为:Ttrs,1=(321.88±0.07)K,ΔtrsHm,1=(37.59±0.17)kJ·mol-1,ΔtrsSm,1=(117.24±0.12)J·K-1·mol-1,Ttrs,2=(323.81±0.30)K,ΔtrsHm,2=(12.42±0.02)kJ·mol-1和ΔtrsSm,2=(38.36±0.09)J·K-1·mol-1.用最小二乘法将实验摩尔热容对温度进行拟合,得到热容随温度变化的多项式方程.用此方程进行数值积分,得到此温区每隔5 K的舒平热容值和相对于298.15 K时的热力学函数值.
(C11H23NH3) 2CdCl4 (s) [abbreviation: C11Cd (s)] was synthesized by X-ray single crystal diffraction method, chemical analysis and elemental analysis to confirm its crystal structure and chemical composition .Using its crystallographic data to calculate the lattice energy is: UPOT = 908.18 kJ · mol-1. The use of precision automatic adiabatic calorimeter in the 78 ~ 395 K temperature region of its low temperature heat capacity, the results show that the complex at The temperature, molar enthalpy and molar entropy of two phase transitions were calculated as follows: Ttrs, 1 = (321.88 ± 0.07) K, ΔtrsHm, 1 = (37.59 ± 0.17) kJ · mol -1, ΔtrsSm 1 = (117.24 ± 0.12) J · K -1 · mol -1 Ttrs 2 = (323.81 ± 0.30) K ΔtrsHm 2 = (12.42 ± 0.02) kJ · mol -1 and ΔtrsSm, 2 = (38.36 ± 0.09) J · K-1 · mol-1. Using the least-squares method, the experimental molar heat capacity was fitted to the temperature to obtain the polynomial equation of the heat capacity with temperature. Numerical integration was performed to obtain the thermal relaxation capacity at 5 K and the thermodynamic function at 298.15 K for this temperature range.