  We perform calculations for the neutron skin of nuclei and its contribution
to atomic parity non-conservation (PNC) in many isotopes of Cs, Ba, Sm, Dy, Yb,
Tl, Pb, Bi, Fr, Ra. Three problems are addressed: i) Neutron-skin induced
errors to single-isotope PNC, ii) Possibility to measure neutron skin using
atomic PNC, iii) Neutron-skin induced errors for ratios of PNC effects in
different isotopes. In the latter case the correlations in the neutron skin
values for different isotopes lead to cancelations of the errors; this makes
the isotopic ratio method a competitive tool in a search for new physics beyond
the standard model.
