Authors:	Kitzmann, Winald R. Heinze, Katja
Title:	Charge-transfer and spin-flip states : thriving as complements
Online publication date:	9-Feb-2023
Year of first publication:	2022
Language:	english
Abstract:	Transition metal complexes with photoactive chargetransfer excited states are pervasive throughout literature. Especially [Ru(bpy) 3 ] 2+ (bpy = 2,2’-bipyridine) with its long-lived triplet metal-toligand charge-transfer emission has been established as a key model complex in the past decades. Meanwhile, interest in luminescence and reactivity of so-called spin-flip metal-centered states has risen dramatically after the Molecular Ruby [Cr(ddpd) 2 ] 3+ (ddpd = N , N ’dimethyl- N , N ’-dipyridin-2-yl-pyridine-2,6-diamine) unveiled design principles to access strong, long-lived emission from photostable chromium(III) complexes. This review contrasts the properties of emissive charge-transfer and spin-flip states illustrated with the prototypical complexes [Ru(bpy) 3 ] 2+ and [Cr(ddpd) 2 ] 3+ . First, we discuss the nature of the relevant excited states, their tunability with regards to energy and lifetime, and their responses to external stimuli. The final section identifies strengths and weaknesses of the charge transfer and spin-flip states in applications such as photoredox catalysis, sensing and circularly polarized luminescence (CPL).
DDC:	540 Chemie 540 Chemistry and allied sciences
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 09 Chemie, Pharmazie u. Geowissensch.
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-8311
Version:	Published version
Publication type:	Zeitschriftenaufsatz
Document type specification:	Scientific article
License:	CC BY-NC-ND
Information on rights of use:	https://creativecommons.org/licenses/by-nc-nd/4.0/
Journal:	Angewandte Chemie : International edition Version of Record (VoR)
Pages or article number:	e202213207
Publisher:	Wiley-VCH
Publisher place:	Weinheim
Issue date:	2022
ISSN:	1521-3773
Publisher DOI:	10.1002/anie.202213207
Relations:	is version of 10.25358/openscience-10133
Appears in collections:	DFG-491381577-H