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Photophysical and electrochemical properties of heteroleptic tris-cyclometalated iridium(III) complexes
Kenneth Dedeian1, Jianmin Shi, Nigel Shepherd
1Army Research Laboratory, 2800 Powder Mill Road, Adelphi, Maryland 20783, USA. kdedeian@art.army.mil
Abstract:
Mixed (difluoro)phenylpyridine/(difluoro)phenylpyrazole tris-cyclometalated iridium complexes were prepared in order to study the effect of fluorination and the pyridine/pyrazole ratio on the emission and electrochemical properties. Increasing fluorination and replacement of pyridine by pyrazole both leads to a widening of the HOMO-LUMO gap and generally leads to a blue shift in emission.
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