Theoretical insight on the electronic structure and photophysical properties of three blue cyclometalated Ir(III) complexes based on the benchmark complex FIrpic

The electronic and photophysical properties of three blue cyclometalated Ir(III) complexes have been investigated by using the density functional theory (DFT) and time dependent density functional theory (TDDFT) methods. Both HOMO and LUMO values of complexes 1, 2 and 3 are in the order of 1 > 2 > 3. The lowest-lying singlet absorption for 1, 2 and three attributed to the configurations of the highest occupied molecular orbital (HOMO) to the lowest unoccupied molecular orbital (LUMO) with the d(Ir)+π(A)→π*(A) [MLCT/ILCT] character. Complexes 1, 2 and three possess almost the same phosphorescence wavelength and transition characters.