Propagation activation energy dienes

Studies of the sodium salts were prevented by technical difficulties. However, reproducible data were reported for the potassium salt. Its propagation is more than 20 times as fast as that of the lithium salt, the increase is caused by lower activation energy, viz. about 12 kcal/mol for the Li+ salt compared with 9 kcal/mol and A = 5.106 M Is 1 for the potassium salt. This gradation seems to be typical for the diene salts it indicates their tight structure that demands a higher rate for larger counter-ions. 

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