Photo‐responsive Single‐Molecule Magnet Showing 0D to 1D Single‐Crystal‐to‐Single‐Crystal Structural Transition and Hysteresis Modulation

Abstract

Photo‐responsive lanthanide‐based single‐molecule magnets (SMM) hold great promise for future switching and memory devices. Herein, we report a dysprosium phosphonate [DyIII(SCN)2(NO3)(depma)2(4‐hpy)2] (1Dy), which features a supramolecular framework containing layers of hydrogen‐bonding network and pillars of π–π interacted anthracene units. The photocycloaddition reaction of anthracene pairs led to a rapid and reversible single‐crystal‐to‐single‐crystal (SC–SC) structural transition to form the 1D coordination polymer [DyIII(SCN)2(NO3)(depma2)(4‐hpy)2]n (2Dy), accompanied by photoswitchable SMM properties with the reduction of effective energy barrier by half and the narrowing of the butterfly‐like hysteresis loop. The diluted sample showed a photo‐induced switch of the blocking temperature (TB) from 3.8 K for 1Dy@Y to 2.6 K for 2Dy@Y. This work may inspire the construction of lanthanide‐based molecular materials with targeted photo‐responsive magnetic properties.

Synergic Light-Induced Electron Transfer and [4 + 4] Cycloaddition toward Switchable Photoluminescence and Single-Molecule Magnet Behavior in a Dy4 Cubane

“…Furthermore, photocontrollable luminescent Ln-SMMs are attractive not only because light can be conveniently and precisely controlled but also owing to the changes in their optical properties. [38][39][40] However, the synergistic modulation of the luminescence and magnetism of Ln-SMMs via light irradiation is extremely di cult. In anthracene-containing Ln complexes, the electron-transfer process and photocycloaddition reactions give rise to remarkable structural changes, leading to drastic variations in the physical properties of the corresponding materials.…”