The ratio
,
where
is the abundance, expressed as the atom fraction of the isotope distinguished by
the subscript numeral, when the two
isotopes are equilibrated between two different chemical species
A
and
B
(or between specific sites
A and
B in the same or different chemical species). The term is most commonly met in connection
with
deuterium solvent
isotope effects, when the fractionation factor
expresses the ratio:
for the exchangeable hydrogen atoms in the chemical species (or sites) concerned.
The concept is also applicable to transition states.
Source:
PAC, 1994, 66, 1077
(Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994))
on page 1115
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by
A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997).
XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic,
J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8.
https://doi.org/10.1351/goldbook.
