Rs. Ruoff et al., THE RELATIONSHIP BETWEEN THE ELECTRON-AFFINITIES AND HALF-WAVE REDUCTION POTENTIALS OF FULLERENES, AROMATIC-HYDROCARBONS, AND METAL-COMPLEXES, Journal of physical chemistry, 99(21), 1995, pp. 8843-8850
Differences in energy for neutral molecule and negative ions upon goin
g from the gas phase to solution, -Delta Delta G(sol), have been calcu
lated from gas phase electron affinities and half-wave reduction poten
tials for a series of fullerenes, aromatic hydrocarbons, metalloporphy
rins, and metal complexes in dimethylformamide (DMF). For those compou
nds with similar charge delocalization, the value of -Delta Delta G(so
l) is constant and equal to 1.76 +/- 0.06 eV for the fullerenes, 1.99
+/- 0.05 eV for the aromatic hydrocarbons and the metalloporphyrins, a
nd 2.19 +/- 0.14 eV for the metal acetylacetonates. The fullerenes for
m a new class of molecules in which the charge is highly delocalized,
and this is demonstrated by the relatively low value of -Delta Delta G
(sol). A procedure for determining adiabatic electron affinities from
reduction potentials, and vice versa, is established. This procedure i
s applied to benzene to give an electron affinity of -0.7 +/- 0.14 eV,
to La@C-82 to give an electron affinity of 3.21 +/- 0.06 eV, and to Y
@C-82 to give an electron affinity of 3.32 +/- 0.06 eV. On the other h
and, a value of E(1/2) = 0.09 +/- 0.14 V vs SCE is predicted for the r
eduction of Ca@C-60 in DMF based upon a reported electron affinity of
3.0 +/- 0.1 eV.