which was oxidized during the process of LMCT excitation reduction of pentacyanoferrate(III)?

[chen ym]

Dear everyone:
I am doing some work on cyano-bridged Fe-Co network soild film. But
now I met a trouble. Please help me!
I found that when the film (detected by IR spectra to know that
FeIII-CN-CoII was main state ) was irradiated by light, something
like LMCT excitation leading reduction of Fe(III) had occurred. That
is, the state of FeII-CN-CoII became to be the main state in the film.
Excuse me, the L of this pentacyanoferrate (III) is
4-(didodecylamino)pyridine.
Since I could not get any information from IR spectra, I could not
image what was oxidized during this process.
Could you give me some information?


Thanks in advance.


Sincerely,

Chen

[LOUIS]

Hard to say what has been oxydised!
Many metal complexes are light sensitive and the effect of the light
depends stongly on the surrounding of the complexating core.Often there
is loss of a ligand by a radical process...if there was a molecule
present to react faster than the reverse reaction (like O2, H2O, amine,
phenol, ...)...it would catch the radical and find another way of decay.
--> Peroxydation, oxydation like H2O2 or R3N->O formation.
This effect should be visual since many complexes are coloured
(especially Co and Fe ones) and a change of shape or a loss of ligand
will alterate the colour.

PhZ

Post by chen ym
I am doing some work on cyano-bridged Fe-Co network soild film. But
now I met a trouble. Please help me!
I found that when the film (detected by IR spectra to know that
FeIII-CN-CoII was main state ) was irradiated by light, something
like LMCT excitation leading reduction of Fe(III) had occurred. That
is, the state of FeII-CN-CoII became to be the main state in the film.
Excuse me, the L of this pentacyanoferrate (III) is
4-(didodecylamino)pyridine.
Since I could not get any information from IR spectra, I could not
image what was oxidized during this process.
Could you give me some information?
Thanks in advance.
Sincerely,
Chen