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Manipulating On/Off Single-Molecule Magnet Behavior in a Dy(III)-Based Photochromic Complex
Yu-Juan Ma1, Ji-Xiang Hu1, Song-De Han1
1College of Chemistry and Chemical Engineering , Qingdao University , Shandong 266071 , P. R. China.
Journal of the American Chemical Society
|January 21, 2020
Summary
Researchers developed new lanthanide-based chain complexes exhibiting reversible room temperature photochromism and photomagnetism. These materials demonstrate switchable single-molecule magnet behavior triggered by light, paving the way for optical switches and magnetic memories.
Area of Science:
- Materials Science
- Magnetism
- Photochemistry
Background:
- Developing materials with switchable magnetic properties at room temperature (RT) is crucial for advanced technologies like optical switches and magnetic memories.
- Exploiting photochromism and photomagnetism to achieve single-molecule magnet (SMM) behavior remains a significant challenge in materials science.
Purpose of the Study:
- To synthesize and characterize novel lanthanide-based chain complexes capable of exhibiting photochromic and photomagnetic properties at RT.
- To investigate the mechanism of light-induced SMM behavior in these materials and explore their potential applications.
Main Methods:
- Solvothermal synthesis of lanthanide (Dy, Gd, Y) chain complexes with hydroxyethylidene diphosphonate (HEDP) and 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPT).
- UV light irradiation experiments to induce photochromic and photomagnetic effects.
- Magnetic property measurements to assess SMM behavior and magnetic relaxation dynamics.
Main Results:
- The synthesized complexes (QDU-1) displayed reversible photochromic and photomagnetic behaviors at RT upon UV irradiation.
- A photoinduced electron transfer (PET) mechanism involving photogenerated radicals was identified as the cause of these phenomena.
- The Dy(III) congener exhibited strong ferromagnetic coupling and slow magnetic relaxation without applied dc fields, demonstrating SMM behavior after RT illumination.
- This study reports the first observation of reversible RT photochromism and photomagnetism in lanthanide-based materials.
Conclusions:
- The developed lanthanide complexes offer a novel platform for light-controlled magnetic properties.
- The observed radical-actuated on/off SMM behavior provides a new strategy for designing light-induced SMMs for potential use in optical switches and magnetic memory devices.
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