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Updated: Apr 10, 2026
Low-energy Cathodoluminescence for OxyNitride Phosphors
Published on: November 15, 2016
Subtle Modulation of Cu4X4L2 Phosphine Cluster Cores Leads to Changes in Luminescence
Kelly Chen1, Jason Shearer1, Vincent J Catalano1
1Department of Chemistry, University of Nevada, 1664 North Virginia Street, Reno, Nevada 89557, United States.
Abstract:
A series of Cu4X4(PPh2py)2 compounds (X = Cl (1), Br (2), I (3), PPh2py = 2-(diphenylphosphino)pyridine) were prepared and characterized using X-ray crystallography, NMR, UV-vis, and luminescence spectroscopy. The copper chloride and bromide clusters have Cu4X4 octahedral cores while the copper iodide clusters contain an unprecedented butterfly shaped core. Crystallization of the copper bromide and iodide clusters from the appropriate solvent produced the solvates 2·2CH2Cl2, 2·2CHCl3, and 3·0.5CH2Cl2 where the presence of the lattice solvate influences the overall structural properties. Using TD-DFT calculations, the emission was assigned to a mixed metal- and halide-to-ligand charge transfer, (M + X)LCT. Subtle differences in the copper core geometry and μ-halide bonding perturb the emissions of these copper(I) halide clusters.
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