Additional Computational Details;Optimised Wavefunctions and the Radial Density-Energy Data Sets from Correlated energy from radial density–energy relations

Details of the fitting process used to derive the hydrogen-like and helium-like energy as a function of the radial density ;The wavefunction for each of the helium-like systems (singlet and triplet state) and the one-electron and two-electron radial energy and radial distribution function data