An electronic transition described approximately as promotion
of an electron from a 'bonding
' orbital to a Rydberg orbital
. Spectral bands corresponding to Rydberg transitions approximately fit the Rydberg
is the wavenumber,
the ionization potential
of the atom or molecular entity,
a principal quantum number,
the Rydberg constant
defect which differentiates between s, p, d, etc., orbitals.
The notation used is, e.g.
PAC, 1996, 68, 2223
(Glossary of terms used in photochemistry (IUPAC Recommendations 1996))
on page 2272