Bragg-Slater radius definitions in Molpro

dftgrid.F90

!> Get Bragg-Slater radii for a specific atom (1--104)
!>
!> \param[in] n  the atom serial number
!> \return  Bragg-Slater radii
!---------------------------------------------------------------------
function bragg(n)
!---------------------------------------------------------------------
  use common_sbragg, only: ialmet
  implicit double precision (a-h,o-z)
  !...  bragg radii (J. C. Slater, Quantum Theory of Molecules and Solids,
  !                  volume 2, table 3-1)
  !                  J Chem Phys 41, 3199 (1964)
  ! values for He, Ne, Ar, Kr, Xe, At, Rn, Fr, Cm++ taken from
  ! webelements.com or reasonable guess
  integer, parameter :: mxbragg=104
  integer :: n
  double precision, parameter :: braggr(mxbragg)= &
       & [0.25d0, 0.25d0, &
       &  1.45d0,1.05d0,0.85d0,0.7d0,0.65d0,0.6d0,0.5d0, 0.45d0, &
       &  1.8d0,1.5d0,1.25d0,1.1d0,1.d0,1.d0,1.d0, 1.d0, &
       &  2.2d0,1.8d0, &
       &  1.6d0,1.4d0,1.35d0,1.4d0,1.4d0,1.4d0,1.35d0,1.35d0,1.35d0,1.35d0, &
       &  1.3d0,1.25d0,1.15d0,1.15d0,1.15d0, 1.15d0, &
       &  2.35d0,2.0d0, &
       &  1.8d0,1.55d0,1.45d0,1.45d0,1.35d0,1.3d0,1.35d0,1.4d0,1.6d0,1.55d0, &
       &  1.55d0,1.45d0,1.45d0,1.40d0,1.40d0, 1.40d0, &
       &  2.6d0,2.15d0, &
       &  1.95d0,(1.85d0,i=1,6),1.8d0,(1.75d0,i=1,7), &
       &  1.55d0,1.45d0,1.35d0,1.35d0,1.3d0,(1.35d0,i=1,3),1.5d0, &
       &  1.9d0, 1.8d0,1.6d0,(1.9d0,i=1,3), &
       &  2.85d0,2.15d0,1.95d0,1.8d0,1.8d0,(1.75d0,i=1,13) ]
  double precision, parameter :: ahl(mxbragg)= &
       & [0.8d0,                                           0.9d0, &
       &  1.8d0,1.4d0,                1.3d0,1.1d0,0.9d0,0.9d0,0.9d0,0.9d0, &
       &  1.4d0,1.3d0,                1.3d0,1.2d0,1.1d0,1.0d0,1.0d0,1.0d0, &
       &  1.5d0, 1.4d0, &
       &  1.3d0,1.2d0,1.2d0,1.2d0,1.2d0,1.2d0,1.2d0,1.1d0,1.1d0,1.1d0, &
       &  1.1d0,1.0d0,0.9d0,0.9d0,0.9d0,0.9d0, &
       &  (1.0d0,i=1,68)]
  double precision, parameter :: alog(mxbragg)= &
       & [5.0d0,                                           5.0d0, &
       &  7.0d0,7.0d0,                5.0d0,5.0d0,5.0d0,5.0d0,5.0d0,5.0d0, &
       &  7.0d0,7.0d0,                5.0d0,5.0d0,5.0d0,5.0d0,5.0d0,5.0d0, &
       &  7.0d0, 7.0d0, &
       &  5.0d0,5.0d0,5.0d0,5.0d0,5.0d0,5.0d0,5.0d0,5.0d0,5.0d0,5.0d0, &
       &  5.0d0,5.0d0,5.0d0,5.0d0,5.0d0,5.0d0, &
       &  (5.0d0,i=1,68)]

  if(n.gt.mxbragg) then
     call error('Nuclear charge too large in Bragg!','bragg')
  end if
  fromang=get_scalar('ANGSTROM')
  if(ialmet.eq.1)then
     !..     produce bragg radius
     bragg = braggr(n)*fromang
  elseif(ialmet.eq.2)then
     !..  Use the values for the Log grid of mura and knowles
     !..        bragg = 1D0
     bragg = alog(n)
  elseif(ialmet.eq.3)then
     !..     use the special Becke values to scale atomic size
     bragg = braggr(n)*fromang*5d-1
     if(n.eq.1) bragg = braggr(n)*fromang
  elseif(ialmet.eq.4)then
     !..     use the Treutler and Ahlrichs value to scale atomic size
     bragg = ahl(n)
  else
     call error('wrong case','function bragg')
  endif
  return
end function bragg