Thermodynamic properties calculations of Cu-based species

Abstract

This work focuses on the thermodynamic property calculations of seven copper-based species, namely copper, copper oxide, copper hydroxide, copper nitrate, and copper hydroxide nitrate. The structures of these species were optimized to achieve stable geometries. The density functional theory (DFT) calculations were employed to obtain various thermodynamic properties such as entropy, enthalpy, Gibbs free energy, and heat capacity at constant pressure. A comparative investigation was performed on the temperature-dependent behavior of key thermodynamic parameters. Species characterized by a higher quantity of atoms tend to demonstrate elevated thermodynamic properties. Copper and copper hydroxide nitrate had higher thermodynamic values than their oxides and other counterparts. It should be noted that the thermodynamic properties of copper hydroxide nitrate were newly computed, and the results showed that the thermodynamic values of the compound structure were higher than their crystalline counterparts. Moreover, due to the large structure size and solid phase, these thermodynamic values exhibited discrepancies with previously calculated computational and experimental values. The thermodynamic property values that depended on temperature were transformed into NASA 7-Coefficient polynomials parameterization. The newly determined thermodynamic data and polynomials provide valuable insights into the thermodynamic behavior of copper-based species. It will help better understand their surface sites and different crystalline structures. Such data can be used to better understand a variety of industrial processes, including combustion, gasification, chemical synthesis, and further to enhance efficiency, reduce costs, and minimize hazardous environmental emissions.