Intermolecular interactions occur between two or more molecules or ions in each state of matter (solid, liquid, gas).
Be cautious not to confuse intramolecular interactions with intermolecular interactions. Intramolecular interactions occur between atoms in a molecule.
Intermolecular interactions can vary from strong electrical attractions and repulsions of ions to very weak dispersion forces. Here's a list of intermolecular interactions in order of decreasing strength:
ion- induced dipole
dipole - induced dipole
If intermolecular interactions did not exist then liquids and solids would only form at unbelievably low temperatures.
Please explore the links below for more detailed descriptions and diagrams.