Indolocarbazole (IC) Derivatives as Promising p‐type Organic Semiconductors: A First‐Principle Study of Their Anisotropic Charge Mobilities

Abstract

AbstractWe present a detailed theoretical study of the structural, charge transport, and optical properties of three indolocarbazole derivatives, viz., 11, 12‐Dihydroindolo[2, 3‐a]carbazole (DIC), 5, 10‐dimethyl‐5,10‐dihydrobenzo[a]indolo[2, 3‐c]carbazole (DMDBIC), and 2,11‐dimethoxydibenzo[2, 3:5,6]pyrrolizino[1, 7‐bc]indolo[1, 2,3‐lm]carbazole (DMDPIC). DFT calculations along with previously reported x‐ray crystal structures reveal that the studied compounds are planar and do not undergo significant changes in structure upon oxidation or reduction. The maximum hole anisotropic charge mobilities for DIC was found to be 0.338 cm2 V−1 s−1 at Φ=175.89° and 355.81° and the maximum electron mobility was 0.181 cm2 V−1 s−1 at Φ=85.94° and 265.85°. For DMDBIC, the predicted maximum anisotropic hole, and electron mobility was 0.501 cm2 V−1 s−1 and 0.775 cm2 V−1 s−1, respectively at Φ=56.72° and 236.63°, while for DMDPIC the predicted maximum anisotropic hole and electron mobility as 1.586 cm2 V−1 s−1 and 0.594 cm2 V−1 s−1, respectively at Φ=0° and 180.0°. The calculated mobilities show that these compounds may be suitable candidates as a p‐type organic semiconductor with better stability than acene compounds.