nly when <a href="#d0psi_rs">d0psi_rs</a> = .true.
a) If a molecule is placed in the corner of the
supercell, there is a discontinuity problem for the
position operator r, which is not periodic. By setting
lshift_d0psi=.true. the discontinuity problem is
solved by shifting the position operator r such that
it is continuous and well defined.
b) If a molecule is placed in the center of the supercell,
there is no discontinuity problem for the position operator r,
and thus you can set lshift_d0psi=.false. But i