Ion-ion interactions, dipole-dipole interactions, hydrogen bonding, London dispersion forces are the four basic intermolecular forces.
- Ion-ion interactions – The interactions between ions (ion-ion interactions) are the easiest to understand: they repel each other like charges and attract opposite charges. Such Coulombic forces act in the gas phase over relatively long distances.
- Dipole-dipole interactions – Dipole-dipole interactions describe the miscibility of polar solvents and their interactions resulting in characteristic parameters like melting points, boiling points, etc.
- Hydrogen bonding – Hydrogen bonding is a special type of attraction dipole-dipole between molecules, not a covalent bond to an atom of hydrogen.
London dispersion forces – Extremely weak attractive forces between atoms or molecules caused by the electrostatic attraction between temporary induced dipoles.