27802-00-2Relevant articles and documents
Isolation and characterization of phenyl viologen as a radical cation and neutral molecule
Porter III, William W.,Vaid, Thomas P.
, p. 5028 - 5035 (2005)
The chemical synthesis, isolation, and characterization of phenyl viologen (PV) as a dication, radical cation, and neutral species are described. Single-crystal X-ray diffraction of PV2+2Cl-H 2O and PV.+PF6-.pyridine reveals the expected differences in bond lengths and also a structural change from two coplanar central rings in PV.+ to a twist of 36° between the two central rings in PV2+. The phenyl viologen radical cation exhibits behavior characteristic of many radical cations, including weak π-dimerization in the solid state and reversible π-dimerization in solution. Electrical conductivity measurements of neutral phenyl viologen, the first such measurements of a neutral viologen, reveal that it is a significantly better conductor than the radical cation. Differences in geometric relaxation during charge transfer offer a possible explanation for the higher conductivity of the neutral viologen.