Available pseudopotentials:
Ru.pbe-n-van.UPF (details)
Perdew-Burke-Ernzerhof (PBE) exch-corr nonlinear core-correction Vanderbilt ultrasoft
Ru.pw91-n-van.UPF (details)
Perdew-Wang 91 gradient-corrected functional nonlinear core-correction Vanderbilt ultrasoft