Dear
Dakims;
In the case of Eugenol for a color influence only the
Methoxy- group is of relevance and counts in ortho position with
7 till
15nm. Such a small change the eye is not able to detect.
Much more important is therefore that the “
Phenolate” Ion has a big influence (enlarging the chromophor) of the basic color. As
Crn+ similar as
Mon+ can coordinate till (as I know)
8 Ligands, the finally brown (
a very unspecific color! – a very, very broad absorption) is easily indicated.
But for all possible
Coordination Numbers you must ask good specialists in
Coordination Chemistry.
I can also
not “calculate” how stabile the “Phenolate” Ion against oxidation (on air) will be in such a complex, because that would even more shift/broaden the absorption too.
You may also study the following reference: "
Complex (chemistry)”
Good Luck!
ARGOS
++