Molecules (Oct 2022)

Modulating the Inclusive and Coordinating Ability of Thiacalix[4]arene and Its Antenna Effect on Yb<sup>3</sup>-Luminescence via Upper-Rim Substitution<xref rid="fn+-20221012160304-1908848" ref-type="fn">+</xref>

  • Sergey N. Podyachev,
  • Svetlana N. Sudakova,
  • Rustem R. Zairov,
  • Victor V. Syakaev,
  • Alexey N. Masliy,
  • Michal Dusek,
  • Aidar T. Gubaidullin,
  • Alexey P. Dovzhenko,
  • Daina N. Buzyurova,
  • Dmitry V. Lapaev,
  • Gulnaz Sh. Mambetova,
  • Vasily M. Babaev,
  • Andrey M. Kuznetsov,
  • Asiya R. Mustafina

DOI
https://doi.org/10.3390/molecules27206793
Journal volume & issue
Vol. 27, no. 20
p. 6793

Abstract

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The present work introduces the series of thiacalix[4]arenes (H4L) bearing different upper-rim substituents (R = H, Br, NO2) for rational design of ligands providing an antenna-effect on the NIR Yb3+-centered luminescence of their Yb3+ complexes. The unusual inclusive self-assembly of H3L− (Br) through Brπ interactions is revealed through single-crystal XRD analysis. Thermodynamically favorable formation of dimeric complexes [2Yb3+:2HL3−] leads to efficient sensitizing of the Yb3+ luminescence for H4L (Br, NO2), while poor sensitizing is observed for ligand H4L (H). X-ray analysis of the single crystal separated from the basified DMF solutions of YbCl3 and H4L(NO2) has revealed the transformation of the dimeric complexes into [4Yb3+:2L4−] ones with a cubane-like cluster structure. The luminescence characteristics of the complexes in the solutions reveal the peculiar antenna effect of H4L(R = NO2), where the triplet level at 567 nm (17,637 cm−1) arisen from ILCT provides efficient sensitizing of the Yb3+ luminescence.

Keywords