Theoretical insights into the electronic structure and photophysical properties of a series of tetranuclear Cu(I) complexes

The electronic structure and photophysical properties of four tetranuclear Cu(I) complexes have been investigated by using density functional theory and time-dependent density functional theory calculations. The four complexes are tetranuclear structure with four Cu(I) centers bridged by four chlorine atoms. Complex 3 has the strongest electron injection ability due to the largest electron affinity value. The lowest lying singlet -> singlet absorption of complexes 1-4 is located at 412, 395, 509, and 578 nm, respectively. The lowest energy emissions of complexes 1-4 are localized at 495, 511, 615, and 619 nm, respectively. The calculated results show that the complex 4 possibly possesses a high phosphorescence quantum efficiency. This study is useful for obtaining a further understanding of the effect of various substituents of ligands on electronic structure and photophysical properties to search for good Cu(I) complexes in organic light-emitting devices.