Azide ion replacement

The Jencks clock was developed into a technique whereby the lifetimes of a whole range of oxocarbenium and carbenium ions of moderate stability could measured. Azide ion replaced thiosulfate, as the products were non-ionic and more stable, although the diifusional rate constant for anion-cation recombination of 5 X 10 s in water at 25 °C still applied, and was later confirmed... 

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