We discussed the validity of the Abrikosov-Gorkov formula for the descripti
on of the decreasing of T-c in the d-pairing superconductors. A scaling beh
avior of T-c with the concentration of nonmagnetic impurities has been obta
ined in the unitary limit scattering. The average of the impurities has als
o been discussed in different models and we showed that the validity of the
procedure is sensitive to the ratio R = 2 Angstrom(0)/T-c.