What are the interactions called between molecules that have permanent dipoles?

The interactions that occur between molecules with permanent dipoles are known as permanent dipole-permanent dipole interactions. These types of interactions arise due to the unequal distribution of electron density within molecules, leading to regions of partial positive and partial negative charges. When these polar molecules come into proximity, the positive end of one molecule is attracted to the negative end of another, resulting in a stabilizing interaction.

Permanent dipole interactions are significant in defining the physical properties of substances, such as boiling and melting points. They are typically stronger than dispersion forces, which occur in non-polar molecules, but weaker than hydrogen bonds, which are a specific type of strong dipole interactions involving hydrogen atom bonded to highly electronegative atoms like nitrogen, oxygen, or fluorine. Ionic interactions occur between charged ions and are distinct from the dipole interactions discussed in this context.