Reinmuth notation

Reinmuth notation. In the electrochemical world, the sequence of electrode and/or chemical reactions that occur are described by a simple shorthand code. Simple electron-transfer reactions are called E reactions. In the same shorthand system, a multiple electron-transfer reaction such as Fe " Fe " -> Fe is an EE reaction , i.e. the product of an electron-transfer process itself undergoes a second electron-transfer process. (Note that the two electron-transfer processes might occur at the same time, in which case it is merely an E reaction.) The vanadium pentoxide system illustrated in Figure 6.14 is another example of an EE system. 

Remember Reinmuth notation is read from left to right, so an EC reaction occurs with a chemical reaction following an initial electrode (electron-transfer) reaction. 

Table 6.4 Reinmuth notation for use within mechanistic electrochemistry, where the terms shown can be combined, and the sequence of the steps should be read from left to right (after Reinmuth, W. H., J. Am. Chem. Soc., 79, 6538-6364 (1957)) ...

Reinmuth notation A useful shorthand notation for abbreviating the order of a sequence of electrochemical ( E ) and chemical ( C ) reactions (see Section 6.4.3). The order of a reaction is read from the left of the Reinmuth code to the right. 

An electroactive species may not be initially present in solution, but may be formed by a reaction of the bulk solution species. This class of electrochemical mechanism is described as a CE mechanism in the Testa and Reinmuth notation. An example of a CE mechanism involves the reduction of ethanoic acid in aqueous solutions, in which protons released by the acid in (46) are reduced reversibly in (47) at the electrode surface (see for example Vielstich and John, 1960a,b Daniele et al., 1996). 

The necessity for the somewhat long-winded wording used in SAQ 6.12 explains why Reinmuth first proposed such a shorthand notation (in 1957). 

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