Term: basis function
https://doi.org/10.1351/goldbook.BT06998

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:
1) molecular orbital (http://doi.org/10.1351/goldbook.M03996).
2) slater-type orbital (http://doi.org/10.1351/goldbook.S05710).

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

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. https://doi.org/10.1351/goldbook.BT06998

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