Ac. Ribou et al., INTERVALENCE ELECTRON-TRANSFER IN PENTAAMMINERUTHENIUM COMPLEXES OF DIPYRIDYLPOLYENES, DIPYRIDYLTHIOPHENE, AND DIPYRIDYLFURAN, Inorganic chemistry, 33(7), 1994, pp. 1325-1329
Intervalence transitions have been observed between pentaamminerutheni
um(II) and -ruthenium(III) groups linked by dipyridylpolyenes, dipyrid
ylthiophene, and dipyridylfuran. For all compounds, the comproportiona
tion constants have been determined, to obtain corrected spectra of th
e mixed-valence forms, and the intervalence band profiles have been ob
tained by spectral deconvolution. The longest dipyridylpolyenes (with
3 and 4 double bonds) give only ill-defined bands, which does not allo
w us to reach definitive conclusions on the decay law of the electroni
c interaction with distance. On the contrary, dipyridylthiophene and -
furan present a better resolution of the intervalence transition, whic
h is ascribed to a better coplanarity and rigidity.