๐Ÿ’intro to chemistry review

Instantaneous dipole

Written by the Fiveable Content Team โ€ข Last updated September 2025
Written by the Fiveable Content Team โ€ข Last updated September 2025

Definition

An instantaneous dipole occurs when the electrons in an atom or molecule are distributed asymmetrically at a given moment, creating a temporary dipole. This transient phenomenon leads to induced dipoles in adjacent molecules and results in intermolecular attractions known as London dispersion forces.

5 Must Know Facts For Your Next Test

  1. Instantaneous dipoles are temporary and fluctuate rapidly within a molecule or atom.
  2. The formation of an instantaneous dipole can induce dipoles in neighboring molecules, leading to intermolecular attractions.
  3. These interactions are a key component of London dispersion forces, which occur even in nonpolar molecules.
  4. Instantaneous dipoles depend on the polarizability of the molecule; larger atoms or molecules with more electrons have stronger dispersion forces.
  5. Despite being weak individually, London dispersion forces due to instantaneous dipoles can cumulatively have significant effects on the physical properties of substances.

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