Publications by authors named "R Klingeler"

Novel microporous polymers were synthesized through Yamamoto polymerization of selectively brominated spirofluorene-bridged -heterotriangulenes. Extensive characterization, including combustion analysis, ToF-SIMS, IR, and Raman spectroscopy, confirmed the elemental composition and integrity of the polymers. The amorphous polymers, observed by scanning electron microscopy as globular particles aggregating into larger structures, exhibited remarkable thermal stability (decomposition temperatures > 400 °C) and BET surface areas up to 690 m g.

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Lithium-rich antiperovskites promise to be a compelling class of high-capacity cathode materials due to the existence of both cationic and anionic redox activity. Little is however known about the effect of separating the electrochemical cationic process from the anionic process and the associated implications on the electrochemical performance. In this context, we report the electrochemical properties of the illustrative example of three different (LiFe)SO materials with a focus on separating cationic from anionic effects.

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Spin-orbit coupling in the electronic states of solution-processed hybrid metal halide perovskites forms complex spin-textures in the band structures and allows for optical manipulation of the excited state spin-polarizations. Here, we report that motional narrowing acts on the photoexcited spin-polarization in CHNHPbBr thin films, which are doped at percentage-level with Mn ions. Using ultrafast circularly polarized broadband transient absorption spectroscopy at cryogenic temperatures, we investigate the spin population dynamics in these doped hybrid perovskites and find that spin relaxation lifetimes are increased by a factor of 3 compared to those of undoped materials.

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Single crystals of Cu[Formula: see text]Bi(SeO[Formula: see text])[Formula: see text]O[Formula: see text]Cl were investigated using high-resolution capacitance dilatometry in magnetic fields up to 15 T. Pronounced magnetoelastic coupling is found upon evolution of long-range antiferromagnetic order at [Formula: see text] [Formula: see text] K. Grüneisen analysis reveals moderate effects of uniaxial pressure on [Formula: see text], of 1.

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The mechanistic investigations between Cu(II) and the anisotropic lanthanides (Ln(III)) are not much explored to date. This is due to the complicated energy spectrum which arises due to the orbital angular momentum of anisotropic lanthanides. Interestingly, the exchange coupling in Ln(III)-Cu(II) systems was found to be antiferromagnetic for <4f metal ions and ferromagnetic for ≥4f metal ions, while the net magnitude of strength gradually decreases moving from to .

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