Triboluminescence diketonates

Rare-earth diketonates incorporated into polymers that result in new triboluminescent materials have been investigated by Takada and coworkers . Although some RE + compounds exhibit no TL in powder form, the TL phenomenon has been observed when these compounds are dispersed in a polymer matrix and the TL mechanism is adduced to electron impact caused by discharge due to a high electric field arising from frictional electrification between the fihn and the substrate. 

Eliseeva S V, Pleshkov DN, Lyssenko KA et al (2010) Highly luminescent and triboluminescent coordination polymers assembled from lanthanide p-diketonates and aromatic bidentate o-donor ligands. Inorg Chem 49 9300-9311... 

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