Accession Number : ADA301971

Title :   Dimerized Pi-Complexes in Self Assembled Monolayers Containing Viologens. An Origin of Unusual Waveshapes in the Voltammetry of Monolayers.

Descriptive Note : Technical rept. Jun 93-May 94,

Corporate Author : WYOMING UNIV LARAMIE DEPT OF CHEMISTRY

Personal Author(s) : Tang, Xiaoyan ; Buttry, Daniel A.

PDF Url : ADA301971

Report Date : 08 MAR 1994

Pagination or Media Count : 45

Abstract : Thiol derivatives of viologens self-assemble at gold and silver electrodes to give monolayers with relatively high surface coverages. Lateral interaction of the viologen redox groups in these monolayers is revealed by virtue of the formation of unique pi-complex diners (pi-mers) for the one-electron reduced form of viologens within these monolayers. The presence of these pi-mers is shown to give double-peaked voltammetric waves, and is unambiguously observed in the surface Raman (including SRRS, SERS and SERRS) spectra of these monolayers. The Raman bands due exclusively to the pi-mer as previously reported are assigned to the out-of-phase coupling nodes of the totally symmetric ring modes of the component cation radicals in the pi-mer. jg p.1

Descriptors :   *COMPLEX COMPOUNDS, *VOLTAMMETRY, *DIMERS, CATIONS, SCATTERING, LAYERS, SURFACES, ELECTRODES, SYMMETRY, RINGS, GOLD, SILVER, RAMAN SPECTRA, CHEMICAL RADICALS.

Subject Categories : Polymer Chemistry
      Organic Chemistry
      Electricity and Magnetism
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE