Term: inclusion compound (inclusion complex)
https://doi.org/10.1351/goldbook.I02998

Definition:
A complex in which one component (the host) forms a cavity or, in the case of a crystal, a crystal lattice containing spaces in the shape of long tunnels or channels in which molecular entities of a second chemical species (the guest) are located. There is no covalent bonding between guest and host, the attraction being generally due to van der Waals forces. If the spaces in the host lattice are enclosed on all sides so that the guest species is 'trapped' as in a cage, such compounds are known as clathrates or 'cage compounds'.

Related Terms:
1) crown (http://doi.org/10.1351/goldbook.C01421).
2) cryptand, cryptate (http://doi.org/10.1351/goldbook.C01426).
3) intercalation compounds (http://doi.org/10.1351/goldbook.I03076).
4) complex (http://doi.org/10.1351/goldbook.C01203).
5) host (<em>in biotechnology</em>) (http://doi.org/10.1351/goldbook.H02859).
6) guest (<em>in biotechnology</em>) (http://doi.org/10.1351/goldbook.G02711).
7) van der waals forces (<em>in biotechnology</em>) (http://doi.org/10.1351/goldbook.V06597).
8) clathrates (<em>in biotechnology</em>) (http://doi.org/10.1351/goldbook.C01097).
9) cage (<em>in biotechnology</em>) (http://doi.org/10.1351/goldbook.C00769).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1124 (https://doi.org/10.1351/pac199466051077)

Citation: 'inclusion compound (inclusion complex)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.I02998

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