INCIPIENT MANIFESTATION OF THE SHELL STRUCTURE OF ATOMS WITHIN THE WDA MODEL FOR THE EXCHANGE AND KINETIC-ENERGY DENSITY FUNCTIONALS

The radial electron density obtained for all the atoms of the main gro ups of the Periodic Table through the solution of the Euler equation a ssociated with the nonlocal weighted density approximation (WDA) for t he exchange and kinetic energy density functionals shows an incipient shell structure which is absent in other calculations using kinetic en ergy functionals based on the electronic density. The WDA radial densi ty reveals two local maxima and the position of the first maximum corr elates with the position of the maximum for the Is orbital in the Hart ree-Fock approximation. The cusp condition at the nucleus is fulfilled accurately. Also we study the density-based electron localization fun ction (DELF) as a complementary procedure for the visualization of she lls.