<polar>
 <tolerance_energy help="Energy change as convergence criterion">1e-5</tolerance_energy>
 <tolerance_dipole help="Field change as convergence criterion">1e-5</tolerance_dipole>
 <max_iter help="Maximum number of iterations">512</max_iter>
 <exp_damp help="Thole sharpness parameter">0.39</exp_damp>
</polar>