The complex (C11H18NO)2CuCl4(s) was synthesized. Chemical analysis, elemental analysis, and X-ray crystallography were used to characterize the structure
and composition of the complex. Low-temperature heat-capacities of the compound were measured by an adiabatic calorimeter
in the temperature range from 77 to 400 K. A phase transition of the compound took place in the region of 297–368 K. Experimental
molar heat-capacities were fitted to two polynomial equations of heat-capacities as a function of the reduced temperature
by least square method. The peak temperature, molar enthalpy, and entropy of phase transition of the compound were calculated
to be Ttrs = 354.214 ± 0.298 K, ΔtrsHm = 76.327 ± 0.328 kJ mol−1, and ΔtrsSm = 51.340 ± 0.164 J K−1 mol−1.