Document Type
Conference Proceeding
Language
eng
Format of Original
4 p.
Publication Date
2007
Publisher
American Institute of Physics
Source Publication
AIP Conference Proceedings
Source ISSN
1551-7616
Original Item ID
DOI: 10.1063/1.2836121
Abstract
Spectroelectrochemistry and voltammetry contain both unique and complementary information. For multielectron transfers, information on each electron exchange is only directly accessible in the voltammetric data if the potentials are well separated so that two distinct waves can be observed. If the E°’s are close together, the voltammetric data will contain the sum of the two exchanges which can only be deconvoluted by modeling the system and solving the appropriate equations. On the other hand, the spectroscopic data contains direct information on each electron exchange even when the E°’s are close together. Unfortunately, this information cannot be readily extracted if the intermediate oxidation state does not have a potential region where it is the dominant species. Chemometric methods such as factor analysis though can be used to deduce the spectra of each species even if they don’t dominate in any potential region. Initial work on the application of factor analysis to spectroelectrochemistry has been reported. Traditional methods of electroanalytical analysis are based on models that relate the concentration of electroactive materials to electrode potentials and solution concentrations. The model and parameters are adjusted to obtain the best fit to a model. Chemometric methods such as factor analysis allow the experimenter to determine solution concentrations without knowledge of the precise electrochemical mechanism. The utility of this approach will be demonstrated by the study of a protein, E. coli sulfite reductase hemoprotein, which is capable of transferring two-electrons and the ΔE° values are less than 100 mV, causing the waves to overlap. With these methods more detailed information on the electron transfer rate and associated kinetics processes can be more clearly identified.
Recommended Citation
Ryan, Michael D. and Keesey, Robert L., "Use of Factor Analysis in Multi‐Electron Spectroelectrochemistry" (2007). Chemistry Faculty Research and Publications. 424.
https://epublications.marquette.edu/chem_fac/424
Comments
Published version. Published as part of AIP Conference Proceedings, 2007. DOI. © 2007 American Institute of Physics. Used with permission.