LAUSR

Abstract In recent years new materials for phosphorescent organic light-emitting diodes were found from complexes of carbazole-modified ortho-phenylene derivatives. We investigate theoretically the photo-induced charge transfer in these complexes. The electronically excited states and absorption spectra of tetramer ortho-phenylene (OP) derivatives were first studied by using time-dependent density functional theory calculations with various functionals. The functional that best reproduced the experimental results was found to be ωB97XD, and the assignment of the experimentally observed ultraviolet–visible absorption spectrum was successfully performed in comparison with the theoretically obtained one. We then performed a spectral assignment of carbazole-modified OP derivatives.