Rydberg orbital

https://doi.org/10.1351/goldbook.R05431
For an atom, an orbital with principal quantum number greater than that of any occupied orbital of the @G02704@. For a molecular entity, a @M03996@ which correlates with a Rydberg atomic orbital in an atomic fragment produced by @D01801@. Typically, the extension of the Rydberg orbital is large compared to the size of the atom or molecular entity.
Source:
PAC, 1996, 68, 2223. (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2272 [Terms] [Paper]