Title data
Kurz, Hannah ; Schötz, Konstantin ; Papadopoulos, Ilias ; Heinemann, Frank W. ; Maid, Harald ; Guldi, Dirk M. ; Köhler, Anna ; Hörner, Gerald ; Weber, Birgit:
A Fluorescence-Detected Coordination-Induced Spin State Switch.
In: Journal of the American Chemical Society.
Vol. 143
(2021)
Issue 9
.
- pp. 3466-3480.
ISSN 1520-5126
DOI: https://doi.org/10.1021/jacs.0c12568
Abstract in another language
The response of the spin state to in situ variation of the coordination number (CISSS) is a promising and viable approach to smart sensor materials, yet it suffers to date from insensitive detection. Herein, we present the synthetic access to a family of planar nickel(II) complexes, whose CISSS is sensitively followed by means of fluorescence detection. For this purpose, nickel(II) complexes with four phenazine-based Schiff base-like ligands were synthesized and characterized through solution-phase spectroscopy (NMR and UV–vis), solid-state structure analysis (single-crystal XRD), and extended theoretical modeling. All of them reveal CISSS in solution through axial ligating a range of N- and O-donors. CISSS correlates nicely with the basicity of the axial ligand and the substitution-dependent acidity of the nickel(II) coordination site. Remarkably, three out of the four nickel(II) complexes are fluorescent in noncoordinating solvents but are fluorescence-silent in the presence of axial ligands such as pyridine. As these complexes are rare examples of fluorescent nickel(II) complexes, the photophysical properties with a coordination number of 4 were studied in detail, including temperature-dependent lifetime and quantum yield determinations. Most importantly, fluorescence quenching upon adding axial ligands allows a “black or white”, i.e. digital, sensoring of spin state alternation. Our studies of fluorescence-detected CISSS (FD-CISSS) revealed that absorption-based CISSS and FD-CISSS are super proportional with respect to the pyridine concentration: FD-CISSS features a higher sensitivity. Overall, our findings indicate a favored ligation of these nickel(II) complexes in the excited state in comparison to the ground state.
Further data
Item Type: | Article in a journal |
---|---|
Refereed: | Yes |
Institutions of the University: | Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Inorganic Chemistry IV > Chair Inorganic Chemistry IV - Univ.-Prof. Dr. Birgit Weber Faculties Faculties > Faculty of Biology, Chemistry and Earth Sciences Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Inorganic Chemistry IV |
Result of work at the UBT: | Yes |
DDC Subjects: | 500 Science > 540 Chemistry |
Date Deposited: | 12 Mar 2021 08:17 |
Last Modified: | 08 Feb 2022 12:57 |
URI: | https://eref.uni-bayreuth.de/id/eprint/63907 |