Autoren:	Sikora, Philipp Naumann, Robert Förster, Christoph Heinze, Katja
Titel:	Excited state energy landscape of phosphorescent group 14 complexes
Online-Publikationsdatum:	20-Apr-2023
Erscheinungsdatum:	2023
Sprache des Dokuments:	Englisch
Zusammenfassung/Abstract:	Great progress has been achieved on phosphorescent or photoactive complexes of the Earth-abundant transition metals, while examples for phosphorescent heavy main group element complexes are rare, in particular for group 14 complexes in the oxidation state +II. The known compounds often show only weak phosphorescence with fast non-radiative deactivation. The underlying photophysical processes and the nature of the phosphorescent electronic states have remained essentially unexplored. The present combined photophysical and theoretical study on tin(II) and lead(II) complexes E(bpep) with the dianionic tridentate ligand bpep2− (E = Sn, Pb; H2bpep = 2-[1,1-bis(1H-pyrrol-2-yl)ethyl]pyridine) provides unprecedented insight in the excited state energy landscape of tetrel(II) complexes. The tin complex shows green intraligand charge transfer (ILCT) phosphorescence both in solution and in the solid state. In spite of its larger heavy-atom effect, the lead complex only shows very weak red phosphorescence from a strongly distorted ligand-to-metal charge transfer (LMCT) state at low temperatures in the solid state. Detailed (TD-)DFT calculations explain these observations and delineate the major path of non-radiative deactivation via distorted LMCT states. These novel insights provide rational design principles for tetrel(II) complexes with long-lived phosphorescence.
DDC-Sachgruppe:	540 Chemie 540 Chemistry and allied sciences
Veröffentlichende Institution:	Johannes Gutenberg-Universität Mainz
Organisationseinheit:	FB 09 Chemie, Pharmazie u. Geowissensch.
Veröffentlichungsort:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-8936
Version:	Published version
Publikationstyp:	Zeitschriftenaufsatz
Weitere Angaben zur Dokumentart:	Scientific article
Nutzungsrechte:	CC BY-NC
Informationen zu den Nutzungsrechten:	https://creativecommons.org/licenses/by-nc/4.0/
Zeitschrift:	Chemical science 14 10
Seitenzahl oder Artikelnummer:	2489 2500
Verlag:	RSC
Verlagsort:	Cambridge
Erscheinungsdatum:	2023
ISSN:	2041-6539
DOI der Originalveröffentlichung:	10.1039/d2sc06984a
Enthalten in den Sammlungen:	DFG-491381577-D