Term: relativistic effects
https://doi.org/10.1351/goldbook.RT07093

Definition:
Corrections to exact non-relativistic energy from the fact that inner shell electrons in heavy atoms move with velocities comparable in order of magnitude to the velocity of light. The most important relativistic effect is spin-orbit coupling.

Related Terms:
1) spin-orbit coupling (http://doi.org/10.1351/goldbook.S05870).

Source: PAC, 1999, 71, 1919. 'Glossary of terms used in theoretical organic chemistry' on page 1960 (https://doi.org/10.1351/pac199971101919)

Citation: 'relativistic effects' 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.RT07093

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