Bond strengths, correlation with leaving group

The rate of reaction correlates with the metal-ligand bond strength of the leaving group, in a hnear free energy relationship (LFER, explained in the next section). 

The observed order of ability did not, however, correlate with the P Ka of YH, with the strength of the C—Y bond, or with the polar effect of Y Clearly, leaving group ability even in this simple reaction is a highly complex attribute. 

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