Observation of Anion and Cation Radicals

FIGURE 45. IR spectra of tetracyanoethylene (TCNE) (a) Transmission spectrum of TCNE (b) SNIFTIRS spectrum recorded during the reduction of TCNE in acetonitrile at a platinum electrode (potential pulses between +0.25 V and -0.25 V versus the 0.01 M Ag /Ag reference electrode). 

FIGURE 46. SNIFTIRS spectrum recorded during the oxidation of 2,6-di-r-butyl-4-phenylaniline in acetonitrile at a Pt electrode (potential pulses between 0.0 and 0.8 V versus Ag /Ag).  

Recently, more detailed information has been obtained by Bewick and Pons to elucidate the behavior of TCNE in solutions of TBAF in acetonitrile. For very low concentrations of TCNE, and using polarized light, it was shown that the molecule was adsorbed flat on the platinum surface. 

The infrared spectroscopic techniques which are discussed in this chapter and illustrated by a few selected examples, have been developed very recently (within the past five years in most cases). The feasibility of applying in situ infrared reflectance spectroscopy to the investigation of the electrode/electrolyte interface is now firmly established. 

Since the pioneering work of Bewick et rapid progress has been 

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