Fully relativistic pseudopotentials
Fully relativistic pseudopotentials generated by
the MBK (PRB 47, 6728 (1993)) scheme within LDA (CA19) and GGA (PBE19) which contain
a partial core correction and fully relativistic effects including spin-orbit coupling.
Pseudo-atomic orbitals
The number below the symbol means a cutoff radius (a.u.) of the confinement
potential. These file includes fifteen radial parts for each angular
momentum quantum number l (=0,1,2,3). The basis functions were generated by ADPACK, and
never optimized by OpenMX.
Since Rb_CA19.vps and Rb_PBE19.vps include the 4s, 5p, and 5s states (9 electrons)
as the valence states, the minimal basis set is Rb*.*-s2p1.
Our recommendation for the choice of cutoff radius of basis functions is that
Rb11.0.pao is enough for bulks, but Rb13.0.pao or Rb15.0.pao is preferable
for molecular systems.
Benchmark calculations by the PBE19 pseudopotential with the various basis functions
(1) Calculation of the total energy as a function of lattice constant in the bcc structure,
where the total energy is plotted relative to the minimum energy for each case. a0
and B0 are the equilibrium lattice constant and bulk modulus obtained by fitting to
the Murnaghan equation of state. The difference between Rb11.0-s3p3d2f2 and Rb11.0-s4p3d3f2
in the total energy at the minimum point is 0.0066 eV/atom.
An input file used for the OpenMX calculations can be found at
Rbbcc-EvsV.dat.
For comparison the result by the Wien2k code is also shown, where
the calculation was performed by default setting in the Ver. 9.1 of Wien2k except for
the use of RMT x KMAX of 12.
(2) Calculations of the band dispersion in the bcc structure,
where the non-spin polarized collinear calculation with the lattice constant of 3.150 Ang.
was performed using Rb_PBE19.vps and Rb11.0-s3p3d2f2,
and the origin of the energy is taken to be the Fermi level.
The input file used for the OpenMX calculations can be found at
Rbbcc-Band.dat.
For comparison the result by the Wien2k code is also shown, where
the calculation was performed by default setting in the Ver. 9.1 of Wien2k
except for the use of RMT x KMAX of 12.
