Low-temperature heat capacity and thermal decomposition of crystalline [Er2(His·H+)(H2O)8](ClO4)6·4H2O

The heat capacities of rare earth complex with amino acid histidine, [Er2(His·H+)(H2O)8](ClO4)6·4H2O, were measured with an automatic adiabatic calorimeter from 79 to 320 K. It was found that there was a sudden increment in heat capacity within the temperature range 182–190 K. Thermal decomposition behavior of the complex in nitrogen atmosphere was studied by thermogravimetric (TG) analysis, and a possible decomposition mechanism was suggested according to TG–DTG results.