Details

Autor(en) / Beteiligte

• Ovsyannikov, A. S
• Khariushin, I. V
• Solovieva, S. E
• Antipin, I. S
• Komiya, H
• Marets, N
• Tanaka, H
• Ohmagari, H
• Hasegawa, M
• Zakrzewski, J. J
• Chorazy, S
• Kyritsakas, N
• Hosseini, M. W
• Ferlay, S

Titel

Mixed Tb/Dy coordination ladders based on tetra(carboxymethyl)thiacalix[4]arene: a new avenue towards luminescent molecular nanomagnets

Ist Teil von

• RSC advances, 2020-03, Vol.1 (2), p.11755-11765

Ort / Verlag

England: Royal Society of Chemistry

Erscheinungsjahr

2020

Quelle

EZB Free E-Journals

Beschreibungen/Notizen

• The macrocyclic ligand calix[4]arene ( L1 ) and its sulphur-containing analogue thia[4]calixarene ( L2 ) are promising precursors for functional molecular materials as they offer rational functionalization with various organic groups. Here, we present the first example of lanthanide-based coordination polymers built from the macrocyclic thiacalix[4]arene backbone bearing four carboxylic moieties, namely, ligand H 4 L3 . The combination of H 4 L3 with the Tb 3+ and Dy 3+ cations led to the formation of 1D ladder-type coordination polymers with the formula [Ln III HL3 DMF 3 ]·(DMF) (where DMF = dimethylformamide and Ln = Tb or Dy, denoted as HL3-Tb and HL3-Dy ), which resulted from the coordination of the lanthanide cations with the partially deprotonated ligand HL3 3− that behaved as a T-shape connector. The coordination sphere around the metal was completed by the coordinated DMF solvent molecules. By combining both Tb 3+ and Dy 3+ cations, isostructural heterobimetallic solid solutions HL3-Tb 1− x Dy x were also prepared. HL3-Tb and HL3-Dy showed visible light photoluminescence originating from the f-f electronic transitions of pale green emissive Tb 3+ and pale yellow emissive Dy 3+ with efficient sensitization by the functionalized thia[4]calixarene ligand HL3 . In the HL3-Tb 1− x Dy x solid solutions, the Tb/Dy ratio governed both the emission colour as well as the emission quantum yield, which reached even 28% at room temperature for HL3-Tb . Moreover, HL3-Dy exhibited a slow magnetic relaxation effect related to the magnetic anisotropy of the dodecahedral Dy 3+ complexes, which were well isolated in the crystal lattice by expanded organic spacers. The single crystals of the two isostructural Tb 3+ - and Dy 3+ -based coordination polymers ( HL3-Tb and HL3-Dy ) were structurally characterized, and their photophysical properties were investigated, together with their corresponding solid solutions.