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[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
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(Bis(terpyridine))copper(II) Tetraphenylborate: A Complex Example for the Jahn-Teller Effect.
Andreas Meyer1, Gregor Schnakenburg2, Robert Glaum2
1Institute of Physical and Theoretical Chemistry, University of Bonn , Wegelerstr. 12, Bonn, Germany.
Inorganic Chemistry
|August 15, 2015
Summary
The crystal structure of copper(II) bis(terpyridine) complexes reveals dynamic Jahn-Teller effects influencing octahedral geometry. This study correlates structural and spectroscopic data to explain solvent-dependent behaviors in these copper complexes.
Area of Science:
- Coordination Chemistry
- Crystallography
- Spectroscopy
Background:
- The copper(II) bis(terpyridine) complex, [Cu(tpy)2](BPh4)2, exhibits a complex crystal structure.
- Structural analysis reveals multiple independent [Cu(II)N6] chromophores with varying octahedral geometries.
Purpose of the Study:
- To investigate the temperature-dependent structural and electronic properties of [Cu(tpy)2](BPh4)2.
- To elucidate the relationship between observed crystal structures and the dynamic Jahn-Teller effect in copper(II) complexes.
Main Methods:
- Single crystal X-ray diffraction (XRD) at ambient and low temperatures.
- Temperature-dependent UV/Vis and Electron Paramagnetic Resonance (EPR) spectroscopy.
- Angular Overlap Model (AOM) calculations.
Main Results:
- Six crystallographically independent [Cu(tpy)2](2+) complexes were identified.
- XRD showed apparent compressed octahedral geometry at ambient temperature, transitioning to a mix of compressed and elongated octahedra at 100 K.
- Spectroscopic and computational data suggest dynamic Jahn-Teller distortion of elongated octahedra causes the observed compressed geometry.
Conclusions:
- The apparent compressed octahedral geometry in [Cu(tpy)2](2+) is attributed to dynamic Jahn-Teller effects.
- A comprehensive understanding of solvent-dependent structural variations in these copper complexes is achieved through integrated structural and spectroscopic analysis.
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