Jump to main content
Jump to site search

Issue 12, 2017
Previous Article Next Article

HOMO inversion as a strategy for improving the light-absorption properties of Fe(II) chromophores

Author affiliations

Abstract

A computational study of a series of [Fe(tpy)2]2+ (tpy = 2,2′:6′,2′′-terpyridine) complexes is reported, where the tpy ligand is substituted at the 4, 4′, and 4′′ positions by electron donor (furan, thiophene, selenophene, NH2) and acceptor (carboxylic acid, NO2) groups. Using DFT and TD-DFT calculations, we show that the substitution of heterocyclic π donor groups onto the tpy ligand scaffold leads to marked improvement of the [Fe(tpy)2]2+ absorption properties, characterized by increased molar extinction coefficients, shift of absorption energies to longer wavelengths, and broadening of the absorption spectrum in the visible region. The observed changes in the light absorption properties are due to destabilization of ligand-centered occupied π orbital energies, thus increasing the interactions between the metal t2g (HOMO) and ligand π orbitals. Substitution of extended π-conjugated groups, such as thienothiophene and dithienothiophene, further destabilizes the ligand π orbital energies, resulting in a fully ligand-localized HOMO (i.e., HOMO inversion) and additional improvement of the light absorption properties. These results open up a new strategy to tuning the light absorption properties of Fe(II)-polypyridines.

Graphical abstract: HOMO inversion as a strategy for improving the light-absorption properties of Fe(ii) chromophores

Back to tab navigation

Supplementary files

Publication details

The article was received on 03 Jul 2017, accepted on 03 Oct 2017 and first published on 04 Oct 2017


Article type: Edge Article
DOI: 10.1039/C7SC02926H
Citation: Chem. Sci., 2017,8, 8115-8126
  • Open access: Creative Commons BY-NC license
  •   Request permissions

    HOMO inversion as a strategy for improving the light-absorption properties of Fe(II) chromophores

    S. Mukherjee, D. E. Torres and E. Jakubikova, Chem. Sci., 2017, 8, 8115
    DOI: 10.1039/C7SC02926H

    This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. Material from this article can be used in other publications provided that the correct acknowledgement is given with the reproduced material and it is not used for commercial purposes.

    Reproduced material should be attributed as follows:

    • For reproduction of material from NJC:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the Centre National de la Recherche Scientifique (CNRS) and the RSC.
    • For reproduction of material from PCCP:
      [Original citation] - Published by the PCCP Owner Societies.
    • For reproduction of material from PPS:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the European Society for Photobiology, the European Photochemistry Association, and RSC.
    • For reproduction of material from all other RSC journals:
      [Original citation] - Published by The Royal Society of Chemistry.

    Information about reproducing material from RSC articles with different licences is available on our Permission Requests page.

Search articles by author

Spotlight

Advertisements