The DAFS *f*' and *f*'' functions were isolated using the Kramers-Kronig
method and the resulting *f*' and *f*'' functions were splined to obtain
the corresponding and functions. Because the and
functions contain linear combinations of contributions from the
Cu(1) and Cu(2) sites, simple weighted differences between pairs of
reflections could be used to obtain the site-separated contributions. The
site-separated Cu(1) and Cu(2) Fourier transform magnitudes obtained by
calculating weighted differences of the pairs using the crystallographic
weights in Table i, and then averaging over the
pairs, are shown in Fig. 9. A FEFF calculation of
the Fourier transform magnitudes expected for the *separate* Cu(1) and
Cu(2) sites using the known YBa_{2}Cu_{3}O_{6.6}
structure are also
shown. The agreement is very good and could probably be improved by
allowing the crystallographic weights to vary slightly. These results
clearly demonstrate the potential of EDAFS for site-selective short-range
atomic structural studies.