Molecular Lanthanide Switches for Magnetism and Photoluminescence. (14th February 2023)

• Record Type: Journal Article
• Authors: Münzfeld, Luca; Dahlen, Milena; Hauser, Adrian; Mahieu, Nolwenn; Kuppusamy, Senthil Kumar; Moutet, Jules; Tricoire, Maxime; Köppe, Ralf; La Droitte, Léo; Cador, Olivier; Le Guennic, Boris; Nocton, Grégory; Moreno‐Pineda, Eufemio; Ruben, Mario; Roesky, Peter W.
• Is Part Of: Angewandte Chemie. Volume 135:Number 18(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2023-02-14
• Subjects: Lanthanides -- Magnetism -- Molecular Switches -- Photoluminescence -- Sandwich Compounds; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202218107
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Solvation of [(CNT)Ln(η 8 ‐COT)] (Ln=La, Ce, Nd, Tb, Er; CNT=cyclononatetraenyl, i.e., C9 H9 − ; COT=cyclooctatetraendiid, i.e., C8 H8 2− ) complexes with tetrahydrofuran (THF) gives rise to neutral [(η 4 ‐CNT)Ln(thf)2 (η 8 ‐COT)] (Ln=La, Ce) and ionic [Ln(thf) x (η 8 ‐COT)][CNT] ( x =4 (Ce, Nd, Tb), 3 (Er)) species in a solid‐to‐solid transformation. Due to the severe distortion of the ligand sphere upon solvation, these species act as switchable luminophores and single‐molecule magnets. The desolvation of the coordinated solvents can be triggered by applying a dynamic vacuum, as well as a temperature gradient stimulus. Raman spectroscopic investigations revealed fast and fully reversible solvation and desolvation processes. Moreover, we also show that a Nd:YAG laser can induce the necessary temperature gradient for a self‐sufficient switching process of the Ce(III) analogue in a spatially resolved manner. Abstract : The common organic donor solvent tetrahydrofuran readily replaces the labile cyclononatetraenyl anion from the coordination sphere of trivalent lanthanide ions. Accordingly, [(C9 H9 )Ln(η 8 ‐C8 H8 )] sandwich complexes reversibly form [Ln(thf) x (η 8 ‐C8 H8 )][(C9 H9 )] species upon solvent coordination. Depending on the complexed lanthanide ion, this drastic modulation of the coordination environment can be exploited to switch the photoluminescence properties (Ce, Tb) or magnetic behaviour (Nd, Er) of the parent complex.