Journal article

Authors list: Mikhalyova, EA; Zeller, M; Jasinski, JP; Butcher, RJ; Carrella, LM; Sedykh, AE; Gavrilenko, KS; Smola, SS; Frasso, M; Cazorla, SC; Perera, K; Shi, AN; Ranjbar, HG; Smith, C; Deac, A; Liu, YL; McGee, SM; Dotsenko, VP; Kumke, MU; Müller-Buschbaum, K; Rentschler, E; Addison, AW; Pavlishchuk, VV

Publication year: 2020

Pages: 7774-7789

Journal: Dalton Transactions

Volume number: 49

Issue number: 23

ISSN: 1477-9226

eISSN: 1477-9234

DOI Link: https://doi.org/10.1039/d0dt00600a

Publisher: Royal Society of Chemistry

Abstract: 
A series of tris(pyrazolyl)borate mono-, di- and trinuclear complexes, [Tp(2)Ln](n)X (Ln = Eu, Tb, Gd, Dy, Xn-= various mono-, bis- and tris(beta-diketonates) has been prepared. The Tb(3+)and Dy(3+)complexes are luminescent single molecular magnets (SMM) and exhibit luminescence quantum efficiencies up to 73% for the Tb(3+)and 4.4% for the Dy(3+)compounds. Similar Eu(3+)complexes display bright emission only at lower temperatures. The Dy(3+)and Tb(3+)complexes possess SMM behavior in a non-zero dc field at low temperatures, while the polynuclear Dy(3+)complexes also show slow magnetic relaxation even in zero dc field up to 8 K.U-eff-values determined from dynamic magnetic measurements were up to 31 and 6 cm(-1)for the Dy(3+)and Tb(3+)complexes, respectively. It was found that within a series of Dy(3+)and Tb(3+)compounds,U(eff)and luminescence quantum yields decreased with increasing nuclearity of the compounds and a shortening of the intramolecular Ln-Ln distance.Delta(Orbach)-values estimated from low-temperature luminescence spectra were significantly higher than those obtained from ac magnetic data, which may be due to involvement of additional processes in the relaxation mechanism (quantum tunneling, Raman, direct) reducing the energy barrier. Some of the Tb3+-compounds also display metal-centred electroluminescence, giving them potential as emitting layers in LEDs.

Harvard Citation style: Mikhalyova, E., Zeller, M., Jasinski, J., Butcher, R., Carrella, L., Sedykh, A., et al. (2020) Combination of single-molecule magnet behaviour and luminescence properties in a new series of lanthanide complexes with tris(pyrazolyl)borate and oligo(β-diketonate) ligands, Dalton Transactions, 49(23), pp. 7774-7789. https://doi.org/10.1039/d0dt00600a

APA Citation style: Mikhalyova, E., Zeller, M., Jasinski, J., Butcher, R., Carrella, L., Sedykh, A., Gavrilenko, K., Smola, S., Frasso, M., Cazorla, S., Perera, K., Shi, A., Ranjbar, H., Smith, C., Deac, A., Liu, Y., McGee, S., Dotsenko, V., Kumke, M., ...Pavlishchuk, V. (2020). Combination of single-molecule magnet behaviour and luminescence properties in a new series of lanthanide complexes with tris(pyrazolyl)borate and oligo(β-diketonate) ligands. Dalton Transactions. 49(23), 7774-7789. https://doi.org/10.1039/d0dt00600a