Absolute entropy calculation from liquid state correlation functions

Because entropy is a function of thermodynamic state it can be determined without need for thermodynamic integration. Concepts from information theory relate the entropy of a liquid metal to its correlation functions, which can be accurately determined from ab-initio molecular dynamics. This relationship is equivalent to the "S2" method that has previously been applied to model liquids. We demonstrate the accuracy of the approach by calculating the absolute entropy of liquid aluminum entirely from first principles, and demonstrate excellent
agreement with experimental data.