Self-assembled Transition Metal Coordination Frameworks of ...

Copper(Il) complexes
different species also. However, the simulation is found in good agreement with two
axial Cu(II) species.
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Fig. 4.24. Experimental (black) and simulated best fit (blue) of the EPR spectrum of
complex 10 in DMF at 77 K.
The spectrum of compound 10 resembles a typical axial Cu(II) monomeric
species. However, as the complex is having two metal centers, the possibility of
similar environment around metal centers can lead to spectra like this, the simulation
was done by considering so. However, fragmentation due to lower stability in DMF
can also lead to spectra like this (high g“ values). But, the EPR of the copper is
governed by the chemical nature and charge state of the close-lying ligand atoms to
the metal atom and is not directly correlated with thermodynamic parameters, which
govern stability of metal-ligand complexes [35]. For example, various polyamines
bind to copper with first dissociation constants ranging over 16 orders of magnitude
[35,41] while the EPR parameters do not vary significantly. Thus, arguments based on
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