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Updated: Jul 15, 2026

Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Excited-state distortions of cyclometalated Ir(III) complexes determined from the vibronic structure in luminescence
Xianghuai Wang1, Jian Li, Mark E Thompson
1Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA.
Abstract:
The luminescence spectra of [(tpy)(2)Ir(CN-t-Bu)2](CF(3)SO(3)) in methylcyclohexane glass and frozen n-nonane at 15 K reveal well-resolved vibronic fine structure. The vibronic peaks are assigned by comparison with the vibrational frequencies obtained from Raman and IR spectra and those obtained using DFT electronic structure calculations. The magnitudes of the distortions along the normal coordinates are calculated by fitting the emission spectra using the time-dependent theory of spectroscopy. Broadening effects and the MIME frequency observed at room temperature are interpreted. The most highly distorted normal modes involve atomic motions on the tpy ligand, consistent with the metal to ligand/ligand centered assignment of the electronic transition.
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