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Fully relativistic pseudopotentials

Fully relativistic pseudopotentials generated by
the MBK (PRB 47, 6728 (1993)) scheme within LDA (CA13) and GGA (PBE13) which contain
a partial core correction and fully relativistic effects including spin-orbit coupling.

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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 variationally
optimizing the corresponding primitive basis functions in the single atom and the BCC bulk.
The input files used for the orbital optimization can be found at
Cs_opt.dat
and
Csbcc_opt.dat.
Since Cs_CA13.vps and Cs_PBE13.vps include the 5s, 5p, and 6s states (9 electrons)
as the valence states, the minimal basis set is Cs*.*-s2p1.
Our recommendation for the choice of cutoff radius of basis functions is that
Cs12.0.pao is enough for bulks, but Cs14.0.pao or Cs16.0.pao is preferable
for molecular systems.

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Benchmark calculations by the PBE13 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. a_{0}
and B_{0} are the equilibrium lattice constant and bulk modulus obtained by fitting to
the Murnaghan equation of state. The difference between Cs12.0-s3p2d2f2 and Cs12.0-s3p3d3f2
in the total energy at the minimum point is 0.0045 eV/atom.
An input file used for the OpenMX calculations can be found at
Csbcc-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 R_{MT} x K_{MAX} of 12, for the spherical harmonic
truncation lmax=14 inside the muffin-tin spheres, and lmax=6 outside of the muffin-tin sphere.

**(2) Calculations of the band dispersion in the bcc structure,**
where the non-spin polarized collinear calculation with the lattice constant of 6.045 Ang.
was performed using Cs_PBE13.vps and Cs7.0-s3p2d2f2,
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
Csbcc-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 R_{MT} x K_{MAX} of 12, for the spherical harmonic
truncation lmax=14 inside the muffin-tin spheres, and lmax=6 outside of the muffin-tin sphere.