Relativistic effects in a phosphorescent Ir(III) complex

We compare high field magnetic circular dichroism, absorption, and photoluminescence spectra for Ir(ptz)(3) with time-dependent density functional theory. By gradually turning on the relativistic effects we identify several distinct relativistic effects in the spectra of this complex. We show that relativistic effects must be included to accurately predict the low-temperature spectra. This leads to new insights into the low-lying excitations responsible for the observed phosphorescence, and suggests new avenues to improve the performance of organic light emitting diodes.