Synthesis, structures and photophysical properties of two new Cu(I) complexes

Abstract

Two cationic heteroleptic four-coordinate Cu(I) complexes were successfully synthesized and characterized by 1H NMR, 13C NMR, 31P NMR spectroscopy and mass spectrometry. The crystal structures of the complexes have been determined by single-crystal X-ray diffraction. UV/Visible absorption spectra of these complexes show ligand-centered π-π* and charge transfer transitions. In the solid state the complexes show intense emissions with microsecond-scale lifetime and relatively high efficiency at room temperature. The photophysical behavior at T = 298 and 77 K indicates that the emissions of these complexes are thermally activated delayed fluorescence mixed with phosphorescence.