Title: basis function
Long Title: IUPAC Gold Book - basis function
DOI: 10.1351/goldbook.BT06998
Status: current

Definition
A one-electron function used in the expansion of the molecular orbital function. Basis functions are commonly represented by atomic orbitals (see also Slater-type orbital or Gaussian-type orbital) centered on each atom of the molecule.

Related Terms
- Slater-type orbital: https://goldbook.iupac.org//terms/view/S05710
- molecular orbital: https://goldbook.iupac.org//terms/view/M03996

Source
- PAC, 1999, 71, 1919. 'Glossary of terms used in theoretical organic chemistry' on page 1925 (https://doi.org/10.1351/pac199971101919)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/BT06998/html
- json: https://goldbook.iupac.org/terms/view/BT06998/json
- xml: https://goldbook.iupac.org/terms/view/BT06998/xml

Citation: Citation: 'basis function' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.BT06998
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Accessed: 2026-05-06T21:37:49+00:00