Intermolecular forces are forces of attraction or repulsion that act between neighboring particles (molecules, atoms, or ions). Van der Waals forces are a fundamental aspect of intermolecular interactions, affecting the physical properties of substances, their phase behavior, and many biological and material processes. While individually weak, these forces are important in understanding the behavior of molecules in various states of matter.
While all Van der Waals forces are intermolecular forces, not all intermolecular forces are Van der Waals forces. Specifically:
Van der Waals forces are a type of weak intermolecular force that plays a significant role in the behavior of molecules, particularly in the condensed phases (liquids and solids). These forces are named after Dutch scientist Johannes Diderik van der Waals, who first described them in the context of real gas behavior.
There are three main types of van der Waals forces: London dispersion forces, dipole-dipole interactions, and dipole-induced dipole interactions.
(Session 2025 - 26)