The thermal stability and the solid-solid phase transitions in the [n-C_nH_(2n+1)NH_3]_2CuCl_4 compounds with n=7-12 have been studied by DSC and TG methods.Comparision with C_nZn compounds was made. The nature of three phases of C_9Cuhas been discussed in terms of infrared spectroscopy and the assignment of thephase transitions has been given. The thermal stability of C_nCu is lower than that ofC_nZn and presents an obvious odd-even effect. All of these compounds exhibit twosolid-solid phase transitions in...