DFT/TDDFT investigation on the electronic structures and photophysical properties of phosphorescent platinum(II) complexes with triarylboron/triarylnitrogen-functionalized N-heterocyclic carbene chelate ligands

Abstract Two series of platinum(II) complexes with triarylboron/triarylnitrogen-functionalized N-heterocyclic carbene chelate ligands have been theoretically investigated by using the density functional theory (DFT) and time-dependent DFT (TDDFT) methods. The influence of different substituents (triarylboron-functionalized or triarylnitrogen-functionalized) on the electronic structure and optical properties of Pt(II) complexes was also explored. The results reveal that the different substituents can influence the electron density distributions of frontier molecular orbitals and their energies, resulting in the change of transition character and emission color. The designed complex 1b and 1d are considered to be a potential candidate as deep blue-emitting material.