The radial grid used for the potential and phase shift calculation
by default, which is sufficient for most cases.
However, occasionally there are convergence problems in the atomic background
at very high energies (the background curves upward) and in the phase
shifts for very large atoms. If such convergence problems are encountered
we suggest reducing to 0.03 or even 0.01. This will solve
these problems at the cost of longer computation times (the time is
proportional to ). This option is also useful for testing
and improving convergence of atomic background calculations.
* reduce grid for more accurate background at high energy