The polarographic reduction of conjugated hydrocarbons: VI. Comparison of Hückel's and Wheland's m.o. approximation with experimental half‐wave potentials of various alternant and non‐alternant hydrocarbons

Abstract

On the basis of the results reported in the foregoing papers IV and V and the data obtained by Bergmant) from the reduction of various aromatic hydrocarbons in ethylene glycol mono-methyl ether Maccoll's relationship between the experimental halfwave potential and the root of the m.0. secular equation corresponding to the lowest non-occupied n-electronic level has been investigated in more detail. It is shown that the half-wave potentials of 38 alternant and non-alternant hydrocarbons being reduced according to the mechanism inferred in paper IV satisfy the relationship: = a.y -0.85 Volt The mean value of the resonance parameter y in e.v. for various experimental conditions becomes: 96% dioxan-water -2 27 f 0 076 Cellosolve b) -262 f 0.066 -2.30 f 0.076 -2.54 f 0.090 a) 75% dioxan-water -250 f 0.092 -2.22 f 0.090 a) twice the standard deviation from mean. b) c.f. note c) of table I. The half-wave potentials of the univalent anions of various conjugated hydrocarbons determined by the equilibrium R + e % R in % yo dioxan-water and the half-wave potential of the radical triphenylmethyl fit the relationship: 1 . ) G. J. Hot%& and J. van Schooten, Rec. trav. chim. 71, 1089 (1952); b) ibid.

Sony's Biofuel Cell

“…Redox potentials of the electron mediators can be estimated from equation 1 (9). b a E LUMO + = ε 2 1 [1] where E 1/2 and ε LUMO are the redox potential and LUMO energy, respectively, and a and b are constants.…”

A Bio-Anode Electron Mediator Both with a Lower Redox Potential and with a Higher Catalytic Current Density

“…The redox potential of the electron mediator can be estimated from equation (1). 5 E 1/2 = -aε LUMO + b…”

Electron-transfer reactions of organic compounds

“…The spin densities can then be found and with the measured The experiments cited earlier prove that a radical is formed when acridine and acridan are mixed in the absence of air and the presence of base. Figure 30 shows the well- able that there is not a great deal of derealization into the benzene rings, for ®'-bifluorene is known to be a twisted molecule (170). Theoretical calculations along with polarographic data predict that the two fluorenes are twisted 60° Blanks were not large in ethanol, however, and meaningful ex periments could be performed in that solvent.…”