Distinct photodynamics of κ-N and κ-C pseudoisomeric iron(ii) complexes

2021

Two closely related FeII complexes with 2,6-bis(1-ethyl-1H-1,2,3-triazol-4yl)pyridine and 2,6-bis(1,2,3-triazol-5-ylidene)pyridine ligands are presented to gain new insights into the photophysics of bis(tridentate) iron(II) complexes. The [Fe(N^N^N)2]2+ pseudoisomer sensitizes singlet oxygen through a MC state with nanosecond lifetime after MLCT excitation, while the bis(tridentate) [Fe(C^N^C)2]2+ pseudoisomer possesses a similar 3MLCT lifetime as the tris(bidentate) [Fe(C^C)2(N^N)]2+ complexes with four mesoionic carbenes. Financial support from the Deutsche Forschungsge-meinschaft [DFG, Priority Program SPP 2102] "Light-controlled reactivity of metal complexes" (BA 4467/7-1, LO 714/11-1, …

Gold(II) Porphyrins in Photoinduced Electron Transfer Reactions

2019

Chemistry - a European journal 25(23), 5940 - 5949 (2019). doi:10.1002/chem.201900050

Higher MLCT lifetime of carbene iron(ii) complexes by chelate ring expansion

2021

Combining strong σ-donating N-heterocyclic carbene ligands and π-accepting pyridine ligands with a high octahedricity in rigid iron(ii) complexes increases the 3MLCT lifetime from 0.15 ps in the prototypical [Fe(tpy)2]2+ complex to 9.2 ps in [Fe(dpmi)2]2+12+. The tripodal CNN ligand dpmi (di(pyridine-2-yl)(3-methylimidazol-2-yl)methane) forms six-membered chelate rings with the iron(ii) centre leading to close to 90° bite angles and enhanced iron-ligand orbital overlap.

Gold(ii) in redox-switchable gold(i) catalysis

2019

Chemical communications 55(32), 4615 - 4618 (2019). doi:10.1039/C9CC00283A

Precise Measurement of the D0 and D+ Lifetimes at Belle II

2021

We report a measurement of the D^{0} and D^{+} lifetimes using D^{0}→K^{-}π^{+} and D^{+}→K^{-}π^{+}π^{+} decays reconstructed in e^{+}e^{-}→cc[over ¯] data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The data, collected at center-of-mass energies at or near the ϒ(4S) resonance, correspond to an integrated luminosity of 72  fb^{-1}. The results, τ(D^{0})=410.5±1.1(stat)±0.8(syst)  fs and τ(D^{+})=1030.4±4.7(stat)±3.1(syst)  fs, are the most precise to date and are consistent with previous determinations.

Ground- and Excited-State Properties of Iron(II) Complexes Linked to Organic Chromophores

2020

Two new bichromophoric complexes, [Fe(bim-ant)2]2+ and [Fe(bim-pyr)2]2+ ([H2-bim]2+ = 1,1′-(pyridine-2,6-diyl)bis(3-methyl-1H-imidazol-3-ium); ant = 9-anthracenyl; pyr = 1-pyrenyl), are investigate...

Cover Feature: Excited‐State Kinetics of an Air‐Stable Cyclometalated Iron(II) Complex (Chem. Eur. J. 51/2019)

2019

Structure and reactivity of a mononuclear gold(II) complex.

2017

Mononuclear gold(II) complexes are very rare labile species. Transient gold(II) species have been suggested in homogeneous catalysis and in medical applications, but their geometric and electronic structures have remained essentially unexplored: even fundamental data, such as the ionic radius of gold(II), are unknown. Now, an unprecedentedly stable neutral gold(II) complex of a porphyrin derivative has been isolated, and its structural and spectroscopic features determined. The gold atom adopts a 2+2 coordination mode in between those of gold(III) (four-coordinate square planar) and gold(I) (two-coordinate linear), owing to a second-order Jahn–Teller distortion enabled by the relativistical…

Molecular dynamics and reverse Monte Carlo modeling of scheelite-type AWO4(A = Ca, Sr, Ba) WL3-edge EXAFS spectra

2016

Classical molecular dynamics (MD) and reverse Monte Carlo methods coupled with ab initio multiple-scattering extended x-ray absorption fine structure (EXAFS) calculations were used for modeling of scheelite-type AWO4 (A = Ca, Sr, Ba) W L 3-edge EXAFS spectra. The two theoretical approaches are complementary and allowed us to perform analysis of full EXAFS spectra. Both methods reproduce well the structure and dynamics of tungstates in the outer coordination shells, however the classical MD simulations underestimate the W–O bond MSRD due to a neglect of quantum zero-point-motion. The thermal vibration amplitudes, correlation effects and anisotropy of the tungstate structure were also estimat…

Excited-State Kinetics of an Air-Stable Cyclometalated Iron(II) Complex.

2019

The complex class [Fe(N^N^C)(N^N^N)]+ with an Earth-abundant metal ion has been repeatedly suggested as a chromophore and potential photosensitizer on the basis of quantum chemical calculations. Synthesis and photophysical properties of the parent complex [Fe(pbpy)(tpy)]+ (Hpbpy=6-phenyl-2,2'-bipyridine and tpy=2,2':6',2''-terpyridine) of this new chromophore class are now reported. Ground-state characterization by X-ray diffraction, electrochemistry, spectroelectrochemistry, UV/Vis, and X-ray spectroscopy in combination with DFT calculations proves the high impact of the cyclometalating ligand on the electronic structure. The photophysical properties are significantly improved compared to …

Electrochemical Reduction and Oxidation of Ruddlesden–Popper-Type La2NiO3F2 within Fluoride-Ion Batteries

2021

Within this article, it is shown that an electrochemical defluorination and additional fluorination of Ruddlesden–Popper-type La2NiO3F2 is possible within all-solid-state fluoride-ion batteries. St...

Understanding and exploiting long-lived near-infrared emission of a molecular ruby

2018

Coordination chemistry reviews 359, 102 - 111 (2018). doi:10.1016/j.ccr.2018.01.004

CCDC 2050317: Experimental Crystal Structure Determination

2021

Related Article: Philipp Dierks, Ayla Kruse, Olga S. Bokareva, Mohammed J. Al-Marri, Jens Kalmbach, Marc Baltrun, Adam Neuba, Roland Schoch, Stephan Hohloch, Katja Heinze, Michael Seitz, Oliver Kühn, Stefan Lochbrunner, Matthias Bauer|2021|Chem.Commun.|57|6640|doi:10.1039/D1CC01716K

CCDC 1520924: Experimental Crystal Structure Determination

2017

Related Article: Sebastian Preiß, Christoph Förster, Sven Otto, Matthias Bauer, Patrick Müller, Dariush Hinderberger, Haleh Hashemi Haeri, Luca Carrella, Katja Heinze|2017|Nature Chemistry|9|1249|doi:10.1038/nchem.2836

CCDC 1904835: Experimental Crystal Structure Determination

2020

Related Article: Jakob Steube, Lukas Burkhardt, Ayla Päpcke, Johannes Moll, Peter Zimmer, Roland Schoch, Christoph Wölper, Katja Heinze, Stefan Lochbrunner, Matthias Bauer|2019|Chem.-Eur.J.|25|11826|doi:10.1002/chem.201902488

CCDC 1587133: Experimental Crystal Structure Determination

2018

Related Article: Sven Otto, Matthias Dorn, Christoph Förster, Matthias Bauer, Michael Seitz, Katja Heinze|2018|Coord.Chem.Rev.|359|102|doi:10.1016/j.ccr.2018.01.004

CCDC 2049729: Experimental Crystal Structure Determination

2021

Related Article: Philipp Dierks, Ayla Kruse, Olga S. Bokareva, Mohammed J. Al-Marri, Jens Kalmbach, Marc Baltrun, Adam Neuba, Roland Schoch, Stephan Hohloch, Katja Heinze, Michael Seitz, Oliver Kühn, Stefan Lochbrunner, Matthias Bauer|2021|Chem.Commun.|57|6640|doi:10.1039/D1CC01716K