Isotopic substitution

Isotopic substitution involves replacing an atom in a molecule with another atom of the same element that has a different number of neutrons, called an isotope. Since isotopes have different masses but similar chemical properties, this change can affect physical behaviors such as vibrational frequencies, reaction rates, and spectroscopic properties. For example, replacing hydrogen with deuterium (a heavier isotope) in a compound can influence how it absorbs light or interacts chemically. This technique helps scientists study molecular dynamics and mechanisms without altering the overall chemical structure.