Photoinduced Significant Magnetization Enhancement in a Viologen-Based Photochromic Compound

Abstract

Large enhancement of magnetization at room temperature (RT) is highly desirable for real application of photomagnets, but only one known example shows remarkable enhancement of magnetization at room temperature (>30%). This work has successfully obtained a viologen-based complex which exhibited room temperature photochromism and photomagnetism and realized remarkable enhancement of magnetization at room temperature by photoinduced electron transfer. The present viologen-based complex exhibits the second largest magnetization increasing amplitude of 31.1% at room temperature among electron transfer photochromic systems.

The simultaneous modulation effect of N-substituents on the photochromic and electrochromic properties of naphthalenediimide-based coordination polymers

“…The mechanism of ET photochromic materials can be broadly divided into two categories, intermolecular and intramolecular ET. To the best of our knowledge, the sole intermolecular ET or intramolecular ET has been widely studied in viologen derivatives, 64 PMDs, 65 NDIs, 66 PDIs 67 and 9-anthracene carboxylic acid ligand. 68,69 However, the synergistic effect of intermolecular and intramolecular ET has rarely been reported.…”

Viologen-Based Photochromic Metal–Organic Framework for Antibiotics Detection in Water

“…And this process is reversible, as the colored samples can be restored to their original state after standing in the dark for 8 h. Such chromic behavior is considered to be associated with a photoinduced electron transfer (PET) process in viologenbased coordination polymers. 21,41,42 To elucidate the photochromic mechanism, FT-IR, PXRD, UV−vis, and EPR experiments have been further conducted. Based on the nearly unchanged FT-IR and PXRD results observed for compound 1 before and after exposing to Xe light (abbreviated as 1-Xe), it is supposed that this photochromic property is not caused by structural variation or new chemical bond formation (Figures S8 and S9).…”

Photochromism and Photomagnetism in Two Ni(II) Complexes Based on a Photoactive 2,4,6-Tris-2-Pyridyl-1,3,5-Triazine Ligand

“…Photochromic smart molecules, as one of the famous multifunctional materials, have been widely used in optical switch, information storage, sensor, and other fields. − They can show color changes under light irradiation with reversible changes in physicochemical properties (such as luminescence, − magnetism, − , and conductivity − ). So far, the metal–organic hybrid photochromic family has increased the possibilities for integrating the merits of inorganic and organic units at the molecular scale, providing a platform for researchers to design and create novel photochromic materials with diverse photoresponsive functionalities. − Especially, electron-transfer (ET) photochromic complexes containing viologen ligands and their derivatives have attracted extensive attention. − However, works on this photochromic system constructed by new photoactive ligands are still challenging due to the difficulty of synthesis and serendipity of photochromism.…”