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The singlet–triplet energy differences, ΔEST, of a series of carbazolyl-phthalonitrile (CzPN) derivatives were calculated at the levels of density functional theory (DFT) and time-dependent (TD) DFT using the gap-tuned, range-separated ωB97X functional. The studied CzPN derivatives include 4-(9H-carbazol-9-yl)phthalonitrile (CzPN), 4,5-di(9H-carbazol-9-yl)phthalonitrile (2CzPN), 3,4,5-tris(9H-carbazol-9-yl)phthalonitrile (3CzPN), and 3,4,5,6-tetra(9H-carbazol-9-yl)phthalonitrile (4CzPN). As additional Cz substituents are introduced, both the HOMO–LUMO energy gap, ΔEH–L, and ΔEST continuously decrease. Both natural transition orbital analysis and a quantitative assessment of the local-excitation (LE) and charge-transfer (CT) contributions to the excited states consistently demonstrate that the S1 states of all of the CzPN derivatives have a predominantly CT nature. In contrast, in the T1 state, the LE feature is dominant, but the CT character increases with the number of Cz groups. The decomposition of exc...

By the SOP (system-on-panel) technology with laser crystallization process, all the driver circuits required for 6-bit color QVGA (320 × RGB × 240) LCD are integrated on panel. The integrated data driver comprises a new ramp-driven 6-bit DAC. The characteristics and uniformity of the LTPS (low temperature polycrystalline silicon) has been remarkably enhanced by applying multi-shot ELA (excimer laser annealing) process and surface treatment. The characteristics of the poly-Si TFTs for integration of driver circuits are following: (1) in NMOS, V th ∼ 1 V and mobility ∼ 240 cm 2 /V s, (2) in PMOS, V th ∼ −1.8 V and mobility ∼ 100 cm 2 /V s.