Perspective on carbazole-based organic compounds as emitters and hosts in TADF applications

摘要: The field of organic light-emitting devices (OLEDs) has undergone a remarkable journey since its discovery by Tang and VanSlyke with an alternation utilizing fluorescence phosphorescence as the emitting vehicle. latest generation thermally activated delayed (TADF) materials harvest triplet excited states back into singlet manifold. This booming yielded large array new compounds both emitters hosts. review is limited to TADF at least one carbazole unit donor organized according various acceptor building blocks such cyanophenyl, pyridine, biphenyls, anthraquinone, phenyl(pyridine-2-yl)methanone, benzophenone, xanthon, sulfones, triazines, benzils, dicyanopyrazines, diazatriphenylene, others. A survey carbazole-containing host follows. Density functional theory (DFT) carved out significant role in allowing theoretical prediction ground state properties for applied OLED technology. Time-dependent DFT extends reach model important rationalize light-output For TADF, two fundamental factors are interest: separation frontier molecular orbitals minimal singlet–triplet energy gap (ΔEST). In this review, utilization calculations optimize geometries visualization orbital was surveyed find that B3LYP/6-31G(d) level overwhelmingly used approach. addition, we more in-depth approaches time-dependent (TD-DFT) optimized percentage Hartree–Fock (OHF) long-range corrected hybrid functionals, tuning procedures others attempt best quantify size ΔEST well nature locally (LE) charge-transfer (CT).