A supramolecular chain of dimeric Dy single molecule magnets decorated with azobenzene ligands. Issue 42 (15th October 2019)

• Record Type: Journal Article
• Authors: Huang, Gang; Yi, Xiaohui; Gendron, Frederic; Le Guennic, Boris; Guizouarn, Thierry; Daiguebonne, Carole; Calvez, Guillaume; Suffren, Yan; Guillou, Olivier; Bernot, Kevin
• Is Part Of: Dalton transactions. Volume 48:Issue 42(2019)
• Page Start: 16053
• Page End: 16061
• Publication Date: 2019-10-15
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c9dt03540k
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Dy III dimers decorated with photo-isomerizable azobenzene ligands behave as single-molecule magnets and self-organize into a supramolecular chain. Ab initio calculations, magnetic and optical properties are reported. Abstract : We report the synthesis, ab initio calculations, magnetic and optical characterization of a Dy III -based dimeric compound named DyAZO . The dimers self-organize into a supramolecular chain decorated with photo-isomerizable azobenzene ligands. DyAZO displays single-molecule magnet (SMM) behavior. However, ab initio calculations highlight a quite strong admixture of M J states of the 6 H15/2 level of Dy III ions, the presence of low-lying excited M J states and antiferromagnetic Dy–Dy dipolar coupling. This favors zero-field fast tunneling. Accordingly the Dy-doped analogue YDyAZO (5.5% Dy doping) displays enhanced magnetic relaxation with a hysteresis that is observed at 0.5 K. The influence of the cis - to trans -isomerization of the decorating azobenzene ligand on magnetic properties has been tested for both solid samples and solutions of DyAZO and YDyAZO . This provides hints for the synthesis of future Dy-based photo-isomerizable molecules.