The inductive effect is the donation or withdrawal of electron density through σ (sigma) bonds, driven by differences in electronegativity. It matters because it shifts charge along a chain of bonds and so stabilises or destabilises nearby charges. For example, alkyl groups release electron density through the inductive effect and thereby stabilise an adjacent carbenium ion. It acts through the σ framework, in contrast to resonance, which delocalises electrons through a π system.

诱导效应是指由电负性差异驱动、通过 σ(西格玛)键传递的电子云给予或吸引作用。它之所以重要,是因为它沿一连串键转移电荷,从而稳定或不稳定邻近的电荷。例如,烷基通过诱导效应给出电子云,从而稳定相邻的碳正离子。它通过 σ 骨架起作用,与通过 π 体系使电子离域的共振形成对照。