Infrared spectra
The preliminary identification of [NiL](ClO
4
)
2
complex was done from their IR spectra in Figure 1. There
are IR frequencies of the macrocyclic complex to be shown the presence of sharp band in the 3207 cm
-1
region,
assignable to the coordination of secondary amine stretching mode. The absence of a band in the regions 1720 – 1740
cm
-1
, which is characteristic
Q
(C=O) carbonyl of aldehyde moiety, further confirms the condensation. In the regions
1384 – 1466 cm
-1
and 2874 – 2961 cm
-1
, respectively, the
Q
(C - N) and
Q
(C – H) modes are found. In addition it is
apparent that there is considerable broadening and splitting in the region centered around 1100 cm
-1
with two peaks at
1089 and 1115 cm
-1
in which these regions are assigned to perchlorate ions. An impartant feature is the appearance of
a new band of peak intensity at 506 cm
-1
attributable to
Q
(Ni - N) which assigns for the involvement of nitrogen in
coordination.
Figure 1.
The IR spectrum of [NiL](ClO
4
)
2
complex
Crystal structure description of [NiL](ClO
4
)
2
The ORTEP drawing view of the molecular structure and labelling scheme are given in Figure 2.
Crystallographic data are given in Table 2. The comple crystallizes in
the triclinic and space group
P
1 . In the
cation, the Ni(II) ion is coordinated by four secondary amine nitrogen atoms of the macrocyclic ligand [NiL]
2+
and
the coordination geometry about Ni(1) is a square-planar. The macrocyclic secondary amine adopts
trans-II
configuration with six-membered macrocyclic rings adopting chair conformations. These pendant butyl groups are
similar to those reported for the nickel(II) complex (Yan, Z. et al, 2009). The average Ni-N (macrocycle) bond length
of 1.9310(18) Å is close to the
ca.
1.92 Å of other square-planar macrocyclic nickel complex (Yan, Z. et al, 2009).
220
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