Signifies, with its superscript, the
bonding number, i.e. the sum of the number of skeletal bonds to an atom and the number of hydrogen
atoms associated with it in a
parent hydride, real or hypothetical. Its usage in names of compounds is generally restricted to
non-standard
valence states.
Source:
PAC, 1984, 56, 769
(Treatment of variable valence in organic nomenclature (lambda convention) (Recommendations
1983))
on page 774
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.
