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Precise control over the supramolecular organization of organic semiconducting materials guiding to exclusive face‐on or edge‐on orientation is a challenging task. In the present work, we study the preferential packing of thiophene oligomers induced through rational molecular designing and self‐assembly. The acceptor–donor–acceptor‐type oligomers having 2‐(1,1‐dicyano‐methylene)rhodanine as acceptor (OT1) favored a face‐on packing, whereas that of functionalized with N‐octyl rhodanine (OT2) preferred an edge‐on packing as evident from 2D‐grazing incidence angle X‐ray diffraction, tapping‐mode atomic force microscopy (AFM) and Raman spectroscopy analyses. The oligomers exhibited anisotropic conductivity in the self‐assembled state as an outcome of the preferred orientation, revealed by the conducting AFM experiment. Subtle Self‐Assembly: Face‐on and edge‐on stacked thiophene oligomers were realised by a rational design and validated by 2D‐GIXRD, tapping and conducting AFM and Raman spectroscopy. GIXRD=grazing incidence X‐ray diffraction, AFM=atomic force microscopy. [ABSTRACT FROM AUTHOR]

White electroluminescence from a single molecule is a challenging topic in organic light emitting diode (OLED) research. Herein, we report the white light emission from a carbazole derivative, 9-ethyl-3,6-bis(4-(trifluoromethyl)phenyl)-carbazole (Cz(PhCF 3 ) 2 ), by harvesting both singlet and triplet emissions. The blue fluorescence and a broad emission from room temperature phosphorescence resulted in white light electroluminescence (EL) with a colour coordinate of (0.31, 0.44). We successfully synthesized another molecule namely 1,1 ' -(4,4 ' -(9-ethyl-9H-carbazole-3,6-diyl)bis(4,1-phenylene))diethanone Cz(PhBz) 2 and achieved a four-fold increase in the efficiency of the EL with a substitution change from −Ph-CF 3 to −Ph-CO-Ph with a colour coordinate of (0.29.0.35). The present route for the generation of white light emission from a solution processable single organic molecule utilizing both singlet and triplet excitons offers a promising way to improve the efficiency of future white OLEDs. [ABSTRACT FROM AUTHOR]

Precise control over the supramolecular organization of organic semiconducting materials guiding to exclusive face-on or edge-on orientation is a challenging task. In the present work, we study the preferential packing of thiophene oligomers induced through rational molecular designing and self-assembly. The acceptor-donor-acceptor-type oligomers having 2-(1,1-dicyano-methylene)rhodanine as acceptor (OT1) favored a face-on packing, whereas that of functionalized with N-octyl rhodanine (OT2) preferred an edge-on packing as evident from 2D-grazing incidence angle X-ray diffraction, tapping-mode atomic force microscopy (AFM) and Raman spectroscopy analyses. The oligomers exhibited anisotropic conductivity in the self-assembled state as an outcome of the preferred orientation, revealed by the conducting AFM experiment., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)