A simple way to satisfy Eq. ( ) is to use LRC functionals. These start from a semilocal exchange functional E GGA x , obtained within the generalized gradient approximation (GGA) by replacing the Coulomb potential with a shorter-range attenuated potential. This short-range exchange functional (E GGA,SR x ) is then combined with long-range HF exchange (E HF,LR x ) to afford an XC functional