Supramolecular chemistry deals with "ordered entities that come from the association of two or more chemical species held together by intermolecular forces" and is defined as "the chemistry of molecular assemblies and of the intermolecular link." Supramolecular chemistry is the branch of chemistry that studies chemical systems with a finite number of molecules. The forces responsible for the system's spatial organisation can range from mild intermolecular forces, electrostatic charge, or hydrogen bonding to strong covalent bonding, as long as the electronic coupling strength is moderate in comparison to the component's energy parameters. Noncovalent interactions between small molecules are used in supramolecular chemistry to self-assemble molecular structures.
Surface chemistry is the discipline of chemistry that studies chemical reactions and changes that occur at the interface of two phases, such as solid – gas, solid – liquid, liquid – gas, and so on. Surface chemistry has a wide range of applications in analytical work, medicine, and the paint industry, to name a few.