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Updated: Oct 27, 2025
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The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
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Strongly Red-Emissive Molecular Ruby [Cr(bpmp)2]3+ Surpasses [Ru(bpy)3]2
Florian Reichenauer1, Cui Wang2,3, Christoph Förster1
1Department of Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany.
Journal of the American Chemical Society
|July 23, 2021
Summary
Researchers developed a novel chromium complex, [Cr(bpmp)2]3+, exhibiting highly efficient blue-shifted luminescence. This spin-flip emitter shows superior photophysical properties compared to precious metal complexes for sensing and catalysis.
Area of Science:
- Photochemistry
- Inorganic Chemistry
- Materials Science
Background:
- Controlling photoexcited states is crucial for sustainable technologies.
- Spin-flip states in transition metal complexes are challenging to predict due to complex electronic interactions.
- Developing novel luminescent materials with tunable properties is an active research area.
Purpose of the Study:
- To design and synthesize a novel highly luminescent spin-flip emitter based on a chromium complex.
- To investigate the photophysical properties, including luminescence wavelength, quantum yield, and excited-state lifetime.
- To explore the potential applications of this complex in optical sensing and photo(redox) catalysis.
Main Methods:
- Multireference quantum chemical calculations guided the design of the chromium complex.
- Synthesis and characterization of the [Cr(bpmp)2]3+ complex.
- Photophysical measurements (luminescence spectra, quantum yield, lifetime) in various conditions (acidic D2O, pH variations).
Main Results:
- A novel chromium complex, [Cr(bpmp)2]3+, was synthesized, exhibiting blue-shifted spin-flip luminescence at 709 nm.
- Achieved high photoluminescence quantum yields up to 25% (with ligand deuteration) and millisecond excited-state lifetimes at room temperature.
- Demonstrated ratiometric optical pH sensing by combining the complex with a pH-insensitive emitter.
- The complex showed superior photophysical and redox properties compared to traditional ruthenium-based charge transfer complexes.
Conclusions:
- The developed chromium spin-flip emitter offers a promising alternative to precious metal complexes for advanced applications.
- The tunable photophysical properties and sensing capabilities highlight the potential of earth-abundant metal complexes.
- This work paves the way for the development of molecular ruby analogues in catalysis and sensing.
![[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
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