Correlation between thermal expansion and heat capacity

Abstract

Theoretically predicted linear correlation between the volume coefficient of thermal expansion and the thermal heat capacity was investigated for highly symmetrical atomic arrangements. Normalizing the data of these thermodynamic parameters to the Debye temperature gives practically identical curves from zero Kelvin to the Debye temperature. This result is consistent with the predicted linear correlation. At temperatures higher than the Debye temperature the normalized values of the thermal expansion are always higher than the normalized value of the heat capacity. The detected correlation has significant computational advantage since it allows calculating the volume coefficient of thermal expansion from one experimental data by using the Debye function.