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Updated: Mar 10, 2026

High-resolution Thermal Micro-imaging Using Europium Chelate Luminescent Coatings
Published on: April 16, 2017
A thermochromic europium(iii) room temperature ionic liquid with thermally activated anion-cation interactions
Bernardo Monteiro1, Mani Outis2, Hugo Cruz2
1Centro de Ciências e Tecnologias Nucleares (C2TN), Instituto Superior Técnico, Universidade de Lisboa, Campus Tecnológico e Nuclear, Estrada Nacional 10, ao km 139,7, 2695-066 Bobadela, Portugal. jpleal@ctn.ist.utl.pt.
Abstract:
We report the first example of an observable and reversible case of thermochromism due to the interaction of an alkylphosphonium (P6,6,6,14)+ with a β-diketonate (1,1,1,2,2,3,3-heptafluoro-7,7-dimethyloctane-4,6-dionate-fod) of an europium(iii) tetrakis-β-diketonate room temperature ionic liquid. This thermochromism is characterized by the conversion of a light yellow viscous liquid, at room temperature, to a reddish substance close to 80 °C. The reversibility of this optical effect was highlighted by the thermal stability of the Eu(iii) complex.
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