Electrochemical properties of C[sub 60]H[sub 2] and C[sub 70]H[sub 2[sup 1]]

Journal Article · Thu Dec 23 04:00:00 EST 1993 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100153a003· OSTI ID:5115532

Boulas, P; D'Souza, F; Jones, M T; Kadish, K M ^[1]; Henderson, C C; Cahill, P A ^[2]

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1. Univ. of Houston, TX (United States)
2. Sandia National Lab., Albuquerque, NM (United States)

The electrochemistry of C[sub 60]H[sub 2] and the 1,9- and 7,8-isomers of C[sub 70]H[sub 2] were investigated in DMF/toluene mixtures and the resulting data compared to that of the parent C[sub 60] and C[sub 70] fullerenes under the same solution conditions. Each dihydrogen derivative is reduced via a series of one-electron transfers. The C[sub 60]H[sub 2] undergoes four reversible reductions which occur at E [sub 1/2] = -1.02, -1.46, -2.07, and -2.58 V vs Fe/Fe[sup +]. The two electroreduced isomers of C[sub 70]H[sub 2] are less soluble than electroreduced C[sub 60]H[sub 2], and only three reductions are seen for these compounds in a toluene/DMF mixture. These occur at E[sub 1/2] = -1.04, -1.48, and -1.96 V vs Fe/Fe[sup +] for the 7,8-isomer and at E[sub 1/2] = -1.03, -1.52, and -1.93 V vs Fe/Fe[sup +] for the 1,9-isomer. The electronic effect of these two different structural isomers is not reflected in their electrochemistry since almost identical E[sub 1/2] values are obtained for each reduction process. The stability of the reduced dihydrogen species decreases with an increase of charge, temperature, and/or the DMF content of the toluene/DMF mixture. Singly-reduced C[sub 60]H[sub 2][sup [sm bullet][minus]] is the most stable of the reduced compounds, and its EPR spectrum was measured and compared to the spectrum of C[sub 60][sup [sm bullet][minus]] in neat toluene. The spectrum of C[sub 60]H[sub 2][sup [sm bullet][minus]] is centered at g = 2.000 and has a spectral line width of 3 G at 160 K, as compared to a g = 1.997 and a line width of 5.8 G for C[sub 60][sup [sm bullet][minus]]. 13 refs., 3 figs., 1 tab.

• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5115532
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 97:51; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102 -- Chemical & Spectral Procedures
400201* -- Chemical & Physicochemical Properties
400400 -- Electrochemistry
ALKYLATED AROMATICS
ANIONS
AROMATICS
CARBON
CHARGED PARTICLES
CHEMICAL REACTIONS
CHEMISTRY
DERIVATIZATION
ELECTROCHEMISTRY
ELECTRON SPIN RESONANCE
ELEMENTS
FULLERENES
HYDROCARBONS
IONS
ISOMERS
MAGNETIC RESONANCE
NONMETALS
ORGANIC COMPOUNDS
RADICALS
REDUCTION
RESONANCE
TOLUENE
VOLTAMETRY