Tuning charge transfer properties in symmetric and asymmetric pyrrolo[3,2-b]pyrrole derivatives with hybridized local and charge-transfer characteristics

Symmetric and asymmetric pyrrolo[3,2-b]pyrrole derivatives were designed to study the hybridized local and charge-transfer (HLCT) properties. Carbazole steric hindrance restricted acceptor rotation, suppressing the charge-transfer (CT) component within the HLCT state, while demonstrating the positive role of CT states in enhancing organic scintillator performance.