摘要
The heat capacities of the two complexes, [La 2(Gly) 6(H 2O) 4]^(ClO 4) 6 and [Ho 2(Gly) 6(H 2O) 4](ClO 4) 6·2H 2O (Gly=glycine), were measured by adiabatic calorimetry in the temperature range from 78 to 375 K. A solid solid phase transition was found between 322 87 and 342 29 K for [Ho 2(Gly) 6(H 2O) 4](ClO 4) 6·2H 2O, and the peak temperature, the enthalpy and the entropy of the transition were obtained to be 330 94 K, 11 65 kJ·mol -1 and 35 20 J·K -1 ·mol -1 , respectively. No indication of any phase transition or thermal anomaly was observed for [La 2(Gly) 6(H 2O) 4]^(ClO 4) 6. Thermal stabilities of the two complexes were investigated by thermogravimetry in the temperature range of 40—800 ℃. The possible mechanisms for the thermal decompositions were proposed according to the TG and DTG curves.
The heat capacities of the two complexes, [La 2(Gly) 6(H 2O) 4]^(ClO 4) 6 and [Ho 2(Gly) 6(H 2O) 4](ClO 4) 6·2H 2O (Gly=glycine), were measured by adiabatic calorimetry in the temperature range from 78 to 375 K. A solid solid phase transition was found between 322 87 and 342 29 K for [Ho 2(Gly) 6(H 2O) 4](ClO 4) 6·2H 2O, and the peak temperature, the enthalpy and the entropy of the transition were obtained to be 330 94 K, 11 65 kJ·mol -1 and 35 20 J·K -1 ·mol -1 , respectively. No indication of any phase transition or thermal anomaly was observed for [La 2(Gly) 6(H 2O) 4]^(ClO 4) 6. Thermal stabilities of the two complexes were investigated by thermogravimetry in the temperature range of 40—800 ℃. The possible mechanisms for the thermal decompositions were proposed according to the TG and DTG curves.
基金
theNationalNaturalScienceFoundationofChina (No .2 0 0 73 0 47)
theNaturalScienceFoundationofHunanProvince(No .0 0JJY2 0 115 )
