Nature of Electronic Levels in Ultraviolet Spectra of Hydrogen and Alkyl Halides

Robert S. Mulliken
Phys. Rev. 61, 277 – Published 1 March 1942
PDFExport Citation

Abstract

The nature of the excited electronic levels involved in the ultraviolet absorption spectra of the alkyl and hydrogen halides, also ICl, IBr, BrCl, is discussed. On the basis of band structures in the hydrogen halides, and other facts, it is concluded that the excited orbital is of σ type (sσ?) in the B, C bands, but of pπ type in the D, E bands. For the upper level of the B and C bands, the coupling changes from nearly J, j-like in the iodides to predominantly L, S-like in the chlorides. The tendency toward L, S-like coupling is greater in the hydrogen than in the alkyl halides. For the B, C "satellites" in HCl, a 4pσ excited orbital is indicated. The D, E bands show nearly J, j-like coupling for all halides. The natures of the excited orbitals in the various observed Rydberg series are also discussed. According to Price, two of the most prominent Rydberg series start with the A continuum and with the D, E bands, and so, according to the present study, should have σ and pπ excited orbitals, respectively. It is also concluded that the npπ "non-bonding" orbital in the normal states of the hydrogen halides and other diatomic hydrides probably is slightly bonding.

  • Received 3 December 1941

DOI:https://doi.org/10.1103/PhysRev.61.277

©1942 American Physical Society

Authors & Affiliations

Robert S. Mulliken

  • Ryerson Physical Laboratory, University of Chicago, Chicago, Illinois

References (Subscription Required)

Click to Expand
Issue

Vol. 61, Iss. 5-6 — March 1942

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Journals Archive

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×