Hysteresis Photomodulation via Single-Crystal-to-Single-Crystal Isomerization of a Photochromic Chain of Dysprosium Single-Molecule Magnets

Maher Hojorat; Hassan Al Sabea; Lucie Norel; Kevin Bernot; Thierry Roisnel; Frederic Gendron; Boris Le Guennic; Elzbieta Trzop; Eric Collet; Jeffrey R Long; Stéphane Rigaut

doi:10.1021/jacs.9b10584

Hysteresis Photomodulation via Single-Crystal-to-Single-Crystal Isomerization of a Photochromic Chain of Dysprosium Single-Molecule Magnets

J Am Chem Soc. 2020 Jan 15;142(2):931-936. doi: 10.1021/jacs.9b10584. Epub 2020 Jan 2.

Affiliations

¹ Univ Rennes , INSA Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes) - UMR 6226 , F-35000 Rennes , France.
² Univ Rennes , CNRS, IPR (Institut de Physique de Rennes) - UMR 6251 , F-35000 Rennes , France.
³ Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States.

PMID: 31880442
DOI: 10.1021/jacs.9b10584

Abstract

A one-dimensional coordination solid 1_c is synthesized by reaction of a bispyridyl dithienylethene (DTE) photochromic unit with the highly anisotropic dysprosium-based single-molecule magnet [Dy(Tp^py)F(pyridine)₂]PF₆. Slow magnetic relaxation characteristics are retained in the chain compound 1_c, and photoisomerization of the bridging DTE ligand induces a single-crystal-to-single-crystal transformation that can be monitored using photocrystallography. Notably, the resulting chain compound 1_o exhibits faster low-temperature relaxation than that of 1_c, which is apparent in magnetic hysteresis data collected for both compounds as high as 4 K. Ab initio calculations suggest that this photomodulation of the magnetic relaxation behavior is due to crystal packing changes rather than changes to the crystal field splitting upon ligand isomerization.