3.2. IR Spectral Studies
IR spectra in the region 4000 - 400 cm
–1
have been re-
corded for the ligand and its complexes and the assignments of the observed frequencies have been made to
specific group vibrations by comparison with the spectra
of related complexes. The IR spectrum of the ligand
showed a shoulder at 1597 cm
–1
assigned to υ(C = N) of
the azomethine stretching vibration, beside a band at
1049 cm
–1
due to C-O-C stretching frequency. These two
bands are shifted to higher or lower wave numbers in the
complexes indicating the participation of the azomethine
nitrogen in coordination [29] and the oxygen of the ether
group, Table 2. On the other hand, the IR spectra of the
complexes exhibited new non-ligand bands in the range
432 - 467 cm
–1
and in the range 492 - 594 cm
–1
assigned
as M-O and M-N stretching vibrations, respectively. There-
fore, it can be concluded that (L) ligand binds to the
metal ions through azomethine N and the ether O and the
ligand behaves as neutral tetradentate ligand.