Pseudopotentials for simulations of materials at extreme conditions*

The ONCVPSP approach [1] has been extended to permit deep core electrons to be active and to accurately reproduce atomic scattering properties to high energies. The basic principles of generalized norm conservation and systematic convergence optimization have been preserved. The original algorithms have been revised to permit consistent optimization of multiple pseudo wave functions for each angular momentum. Ground-state benchmark performance with active deep levels is comparable to that for the original 1 and 2 projector valence plus shallow-core potentials. A confined-atom model has been developed to compare pseudo and all-electron atoms at extreme temperatures and pressures, and verifies the accuracy of the extended potentials up to temperatures which ionize deep core electrons. The open-source oncvpsp-4.0.1 code incorporating these advances for scalar- and fully-relativistic treatments is now available.
1. D. R. Hamann, Phys. Rev. B 88, 085117 (2013).