Title data
Petzold, Holm ; Djomgoue, Paul ; Hörner, Gerald ; Lochenie, Charles ; Weber, Birgit ; Rüffer, Tobias:
Bis-meridional Fe²⁺ spincrossover complexes of phenyl and pyridyl substituted 2-(pyridin-2-yl)-1,10-phenanthrolines.
In: Dalton Transactions.
Vol. 47
(2018)
Issue 2
.
- pp. 491-506.
ISSN 1477-9234
DOI: https://doi.org/10.1039/C7DT02320K
Abstract in another language
A series of Fe2+ SCO complexes of substituted 2-(pyridin-2-yl)-1,10-phenanthrolines 2 was prepared and the SCO (spincrossover) properties were characterized in the solid state (X-ray crystallography, SQUID magnetometry) and in solution (VT-1H NMR spectroscopy), augmented by theoretical modelling. Bis-meridional coordination of the tridendate 2a–c and tetradentate 2d ligands gives octahedral and distorted trigonal-dodecahedral complexes [Fe(2)2]2+, respectively, which were identified as SCO complexes with the transition temperature T1/2 below room temperature. SCO in the solid state is limited to bromo-substituted [Fe(2a)2]2+ (Dalton Trans., 2017, 46, 6218–6229) and [Fe(2b)2]2+ with a pyridine-appended phenyl group, whereas solution state NMR studies reveal SCO behaviour for all complexes, which is in agreement with DFT derived results. As anticipated from its N6(+2) coordination in the HS state, DFT structure modelling of [Fe(2d)2]2+ identified deviation from a structure-conserving SCO reaction coordinate; that is, Fe–N breathing is accompanied by a change in the coordination number. Accordingly, a remarkably slow SCO is observed in [Fe(2d)2]2+, owing to an extended coordinate. De-novo defined characteristic temperatures T(τHSLS) are introduced as structure-dependent parameters deemed to define the onset of phenomenological “slow” SCO. The rich phenomenology of the NMR spectra of [Fe(2)2]2+ is identified to be largely controlled by the dynamics of spin-state exchange and a qualitative illustration of the NMR-reporters of SCO is suggested.
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: | 22 Jan 2018 14:41 |
Last Modified: | 09 Oct 2019 12:05 |
URI: | https://eref.uni-bayreuth.de/id/eprint/41910 |