A series of copper(I) complexes with electron donor/acceptor embedded ligands Synthesis, photophysical and electroluminescent properties

In this paper we report the synthesis of four diimine ligands incorporated with an electron donor/acceptor as well as their corresponding Cu(I) complexes with bis(2-(diphenylphosphanyl)phenyl) ether as an ancillary ligand resulting in four phosphorescent Cu(I) complexes Their crystal structures as well as photophysical and thermal properties are discussed in detail Experimental data and theoretical calculations confirm that electron donor moieties and limited conjugation system may self-restrict geometry relaxation in excited states leading to narrowed and blue-shifted emission bands On the other hand electron acceptor moieties and large coplanar conjugation system are ineffective in restricting geometry relaxation leading to broadened and red-shifted emission bands However the introduction of electron donors compromises thermal stability of Cu(I) complexes We also explore one of the Cu(I) complexes as a dopant for electroluminescence application and a maximum luminance of 680 cd/m(2) peaking at 620 nm is achieved (C) 2010 Elsevier B V All rights reserved