Site-Selective Orbital Interactions in an Ultrathin Iron-Carbene Photosensitizer Film

Temperton, Robert H.; Rosemann, Nils W.; Guo, Meiyuan; Johansson, Niclas; Fredin, Lisa A.; Prakash, Om; Wärnmark, Kenneth; Handrup, Karsten; Uhlig, Jens; Schnadt, Joachim; Persson, Petter

doi:10.1021/acs.jpca.0c00803

Cited by 13 publications

(26 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These non-trivial metal-ligand bonding properties were further detailed in a recent study combining optical characterization with resonant photoemission X-ray spectroscopy of thin films of complex 25(III). [96] This study firstly confirmed the integrity of the Fe(III) oxidation state for thin films, thus broadening the potential range of viable applications towards thin film technologies significantly. Secondly, the presented X-ray spectroscopic results elucidated the involvement of the different ligand constituents to different molecular orbital components of the valence electronic structure in significant detail.…”

Section: Photoluminescent Fe(iii) Hexa-carbene Complexessupporting

confidence: 56%

Photophysics and Photochemistry of Iron Carbene Complexes for Solar Energy Conversion and Photocatalysis

et al. 2020

Self Cite

View full text Add to dashboard Cite

Earth-abundant first row transition metal complexes are important for the development of large-scale photocatalytic and solar energy conversion applications. Coordination compounds based on iron are especially interesting, as iron is the most common transition metal element in the Earth’s crust. Unfortunately, iron-polypyridyl and related traditional iron-based complexes generally suffer from poor excited state properties, including short excited-state lifetimes, that make them unsuitable for most light-driven applications. Iron carbene complexes have emerged in the last decade as a new class of coordination compounds with significantly improved photophysical and photochemical properties, that make them attractive candidates for a range of light-driven applications. Specific aspects of the photophysics and photochemistry of these iron carbenes discussed here include long-lived excited state lifetimes of charge transfer excited states, capabilities to act as photosensitizers in solar energy conversion applications like dye-sensitized solar cells, as well as recent demonstrations of promising progress towards driving photoredox and photocatalytic processes. Complementary advances towards photofunctional systems with both Fe(II) complexes featuring metal-to-ligand charge transfer excited states, and Fe(III) complexes displaying ligand-to-metal charge transfer excited states are discussed. Finally, we outline emerging opportunities to utilize the improved photochemical properties of iron carbenes and related complexes for photovoltaic, photoelectrochemical and photocatalytic applications.

show abstract

Section: Photoluminescent Fe(iii) Hexa-carbene Complexessupporting

confidence: 56%

Photophysics and Photochemistry of Iron Carbene Complexes for Solar Energy Conversion and Photocatalysis

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…4 as a basis for the subsequent discussions of the RPES data. Unlike , which we have previously discussed in detail 35 , is a closed-shell complex. The LUMO (lowest unoccupied MO) is almost entirely of character and located on the bpy ligand (MO-235).…”

Section: Resultsmentioning

confidence: 88%

“…XAS and emerging time-resolved X-ray techniques 27 have contributed to a better understanding of the properties of iron–carbene photosensitisers in terms of electronic structure 28 – 31 , excited-state deactivation pathways 32 , and excited-state dynamics such as hot branching 33 and wave packet oscillations 34 . We have also used resonant photoelectron spectroscopy (RPES) to probe site-selective orbital interactions in 35 .…”

Section: Introductionmentioning

confidence: 99%

“…However, RPES studies have rarely probed both the metal and ligand contributions allowing electronic structure features from each to be placed on a common binding energy axis. Recent studies of hexacyano cobaltate 44 and 35 suggest this is a useful experimental strategy providing information about the overlap of metal/ligand derived orbitals as well the mixing of occupied and unoccupied states. Here, we expand this strategy to include a comprehensive RPES study of an open-shell transition metal complex.…”

Section: Introductionmentioning

confidence: 99%

“…For , Fe 2 p RPES is used to probe the central iron atom whilst N 1 s and C 1 s RPES probes the btz and bpy ligands. For , we use Fe 2 p RPES to probe the metal centre, which we connect to our recently published RPES study of the ligand interactions 35 . The similar ligand environments in the two complexes allow a good comparison of and oxidation states.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Resonant X-ray photo-oxidation of light-harvesting iron (II/III) N-heterocyclic carbene complexes

Temperton

Guo

D’Acunto

et al. 2021

Sci Rep

Self Cite

View full text Add to dashboard Cite

Two photoactive iron N-heterocyclic carbene complexes $${[\hbox {Fe}^{{{\rm{II}}}}(\hbox {btz})_2(\hbox {bpy})]^{2+}}$$ [ Fe II ( btz ) 2 ( bpy ) ] 2 + and $${[\hbox {Fe}^{{\rm{III}}}(\hbox {btz})_3]^{3+}}$$ [ Fe III ( btz ) 3 ] 3 + , where btz is 3,3’-dimethyl-1,1’-bis(p-tolyl)-4,4’-bis(1,2,3-triazol-5-ylidene) and bpy is 2,2’-bipyridine, have been investigated by Resonant Photoelectron Spectroscopy (RPES). Tuning the incident X-ray photon energy to match core-valence excitations provides a site specific probe of the electronic structure properties and ligand-field interactions, as well as information about the resonantly photo-oxidised final states. Comparing measurements of the Fe centre and the surrounding ligands demonstrate strong mixing of the Fe $${\hbox {t}_{{\rm{2g}}}}$$ t 2 g levels with occupied ligand $$\pi$$ π orbitals but weak mixing with the corresponding unoccupied ligand orbitals. This highlights the importance of $$\pi$$ π -accepting and -donating considerations in ligand design strategies for photofunctional iron carbene complexes. Spin-propensity is also observed as a final-state effect in the RPES measurements of the open-shell $$\hbox {Fe}^{{\rm{III}}}$$ Fe III complex. Vibronic coupling is evident in both complexes, where the energy dispersion hints at a vibrationally hot final state. The results demonstrate the significant impact of the iron oxidation state on the frontier electronic structure and highlights the differences between the emerging class of $$\hbox {Fe}^{{\rm{III}}}$$ Fe III photosensitizers from those of more traditional $$\hbox {Fe}^{{\rm{II}}}$$ Fe II complexes.

show abstract

Nonclassical carbenes as noninnocent ligands

Bezuidenhout

Kleinhans

Karhu

2023

Comprehensive Inorganic Chemistry III

View full text Add to dashboard Cite

Site-Selective Orbital Interactions in an Ultrathin Iron-Carbene Photosensitizer Film

Cited by 13 publications

References 30 publications

Photophysics and Photochemistry of Iron Carbene Complexes for Solar Energy Conversion and Photocatalysis

Photophysics and Photochemistry of Iron Carbene Complexes for Solar Energy Conversion and Photocatalysis

Resonant X-ray photo-oxidation of light-harvesting iron (II/III) N-heterocyclic carbene complexes

Nonclassical carbenes as noninnocent ligands

Contact Info

Product

Resources

About