An inductive effect is an electronic effect due to the polarisation of σ bonds within a molecule or ion. This is typically due to an electronegativity difference between the atoms at either end of the bond. There are two types of inductive effect: +I and –I effect. Atoms or groups which pull electron density towards themselves are considered as exhibiting negative Inductive effect (–I) and groups which push electron density away from themselves exhibit positive Inductive effect (+I).
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