Reverse engineering

One of the great abilities of iDEA is being able to obtain the \(\textit{exact}\) KS potential. This is done by solving the Schrodinger equation exactly, obtaining the exact electron density. From here, the iDEA code then works backwards to see what KS potential would have given this electron density (more details are given here). The reason for doing this is that it allows us to compare the exact reverse-engineered KS potential with that given by approximations, such as the LDA - using this comparison to improve the approximations we’re using.