Designed nonlocal pseudopotentials for enhanced transferability

A pseudopotential generation method is presented which significantly improv es transferability. The method exploits flexibility contained in the separa ble Kleinman-Bylander form of the nonlocal pseudopotential [Phys. Rev. Lett . 48, 1425 (1982)]. By adjusting the functional form of the local potential , we are able to improve the agreement with all-electron calculations. Resu lts are presented for the H, Si, Ca, Zr, and Pb atomic pseudopotentials. Co nfiguration testing, logarithmic derivatives, chemical hardness, and struct ural tests all confirm the accuracy of these pseudopotentials. [S0163-1829( 99) 14715-5].