Searching for Divalent Gold

Apart from the g value, the coupling a (hyperfine splitting = HFS) of the unpaired electron to the gold nucleus ( Au, 7=3/2, 100% natural abundance) should reveal the metal contribution to the unpaired spin. The highest HFS of about 30 to 60 G have been observed for the S-macrocycle coordinated species. 

7 Multiredox-Arrays Cobalt(II)Porphyrin-Fullerene Dyads 

Comparison with analogous investigations on [(TPP)Co] reveals that for the cobalt porphyrin complex [(T BuP)Co] the first electrochemical oxidation occurs metal-centred, leading to a Co(III) species [(T BuP)Co(III)]. The second 

For the dyad M3 the conclusion from the UV-Vis spectra contrasts with the free Co porphyrin complexes. The marked decrease of the Soret band (while split into two) strongly suggests the formation of a porphyrin n cation, i.e. [full-(TrBuP )Co(II)]. The second oxidation then probably leads to the same type of species [full-(TtBuP )Co(III)] as observed for the free Co-porphyiin complexes. 

THPP mcio-Tetra[p-( hexyl)phenyl]porphyrin 

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