Medium Diradical Character, Small Hole and Electron Reorganization Energies and Ambipolar Transistors in Difluorenoheteroles. (4th July 2022)

• Record Type: Journal Article
• Authors: Mori, Sakura; Moles Quintero, Sergio; Tabaka, Naoki; Kishi, Ryohei; González Núñez, Raúl; Harbuzaru, Alexandra; Ponce Ortiz, Rocío; Marín‐Beloqui, Jose; Suzuki, Shuichi; Kitamura, Chitoshi; Gómez‐García, Carlos J.; Dai, Yasi; Negri, Fabrizia; Nakano, Masayoshi; Kato, Shin‐ichiro; Casado, Juan
• Is Part Of: Angewandte Chemie. Volume 134:Number 33(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-07-04
• Subjects: Ambipolar -- Diradical Character -- Electronic Couplings -- Organic Field Effect Transistors -- Reorganization Energies; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202206680
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Four difluorenoheteroles having a central quinoidal core with the heteroring varying as furan, thiophene, its dioxide derivative and pyrrole have shown to be medium character diradicals. Solid‐state structures, optical, photophysical, magnetic, and electrochemical properties have been discussed in terms of diradical character, variation of aromatic character and captodative effects (electron affinity). Organic field‐effect transistors (OFETs) have been prepared, showing balanced hole and electron mobilities of the order of 10 −3 cm 2 V −1 s −1 or ambipolar charge transport which is first inferred from their redox amphoterism. Quantum chemical calculations show that the electrical behavior is originated from the medium diradical character which produces similar reorganization energies for hole and electron transports. The vision of a diradical as simultaneously bearing pseudo‐hole and pseudo‐electron defects might justify the reduced values of reorganization energies for both regimes. Structure‐function relationships between diradical and ambipolar electrical behavior are revealed. Abstract : Diradicals are electrically ambipolar owing to the semiaperture of the π‐electron shell which produces redox amphoteric behaviour and small reorganization energies for hole and electron transports.