A crystalline complex of erbium perchlorate coordinated with glycine, [Er-2(Gly)(6)(H2O)(4)](ClO4)(6)center dot 5H(2)O, has been synthesized. No melting point is observed above room temperature. The heat capacity of the complex was measured by adiabatic calorimetry from 79 K to 369 K, and two peaks centered at 233 K and 325 K were found. The first peak centered at 233 K was a phase transformation peak, and the second was decomposition. The temperature, enthalpy change, and entropy change of the phase transformation were 219.47 K, 17.51 kJ center dot mol(-1), and 79.77 J center dot K-1 center dot mol(-1), and those of the decomposition process were 312.576 K, 94.86 kJ center dot mol(-1), and 303.49 J center dot K-1 center dot mol(-1). The polynomial equations of heat capacity in different temperature ranges, 79.091 K to 217.424 K and 255.606 K to 306.143 K, have been obtained by least-squares fitting. The standard enthalpy of formation was determined to be Delta H-f(m)theta ([Er-2(Gly)(6)(H2O)(4)](ClO4)(6)center dot 5H(2)O, s, 298.15 K) = -7911.13 +/- 2.77 kJ center dot mol(-1) by isoperibol reaction calorimetry.