open access

https://hdl.handle.net/2115/76248

Ligand-Assisted Back Energy Transfer in Luminescent Tb-III Complexes for Thermosensing Properties

英語

thermosensitive materials

2018-12-03

Wiley-Blackwell

Chemistry-A European journal

24(67)

17719-17726

A luminescent Tb-III complex with a hexafluoroacetylacetone (hfa) ligand shows a characteristic back energy transfer (BEnT), which leads to high temperature sensitivity and potential application as a thermosensitive paint. Ligand-assisted BEnT was observed when a phosphine oxide ligand was introduced into Tb(hfa)(3) complex, which was shown to affect the activation energy (Delta E-a) and frequency factor (A) in the BEnT process between Tb-III ion and hfa ligands. According to temperature-dependent emission-lifetime measurements of mononuclear Tb(hfa)(3) complexes with monodentate phosphine oxides and polynuclear Tb(hfa)(3) complexes with bidentate phosphine oxides, the Delta E-a and A values of polynuclear Tb-III complexes were smaller than those of mononuclear Tb-III complexes. Phosphorescence spectra and lifetimes of each Gd(hfa)(3) complex revealed that excited states of hfa ligands in Tb(III)complexes differed from those of the polynuclear Tb-III complexes and mononuclear Tb-III complexes. The differences in the Delta E-a and A values between polynuclear and mononuclear Tb-III complexes were caused by the formation of different excited states, such as delocalization of the excited state in the polynuclear Tb-III complexes and localization of excited states in the mononuclear Tb-III complexes. In particular, small Delta E-a and A values of polynuclear Tb-III complexes provided high, effective activation of the BEnT at low temperature, which resulted in high-sensitive temperature-dependent phosphor materials over a wide temperature range.

学術雑誌論文

Accepted Manuscript

This is the peer-reviewed version of the following article: M. Yamamoto, Y. Kitagawa, T. Nakanishi, K. Fushimi, Y. Hasegawa, Chem. Eur. J. 2018, 24, 17719, which has been published in final form at http://doi.org/10.1002/chem.201804392. This article may be used for non-commercial purposes in accordance with Wiley-VCH Terms and Conditions for Self-Archiving.

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