In supramolecular chemistry, host-guest chemistry describes complexes that are composed of two or more molecules or ions held together in unique structural relationships by hydrogen bonding or by ion pairing or by Van der Waals force other than those of full covalent bonds.

The host component is defined as an organic molecule or ion whose binding sites converge in the complex and the guest component is defined as any molecule or ion whose binding sites diverge in the complex. Compared to immunology the host is the antibody and the guest the antigen.

Suitable hosts have cavities in which a guest can fit:

• Cyclodextrins
• Calixarenes
• Cucurbiturils
• Porphyrins
• Crown ethers

This type of compounds are also called cavitands.

Host-guest chemistry is observed in

• Inclusion compounds
• Intercalation compounds
• Clathrates
• Cryptands
• Molecular tweezers

See also

• Molecular complementarity

supramolecular chemistry