Modeling of Grazing-Incidence X-ray Diffraction from Naphthyl End-Capped Oligothiophenes in Organic Field-Effect Transistors

• DOI: 10.1021/acs.cgd.0c00281
• Publication Date: 2020-05-13T10:30:11Z
• Authors: Michael J. Winokur; Mathias K. Huss-H...; Andreas E. Lauritzen; Mika Torkkeli; Jakob Kjelstrup-H...; Matti Knaapila
• Keywords: Trimer; Molecular mechanics

The structure of two naphthylene-capped oligothiophene, 5,5′-bis(naphth-2-yl)-2,2′- bi- and tri- thiophene, thin-film field-effect transistor assemblies has been studied using modeling in conjunction with grazing incidence X-ray diffraction. Although the well-known herringbone molecular packing motif is observed these films for both compounds, density functional calculations mechanics give evidence a local polymorphic ordering which molecules can be flipped 180° about long axis. In one case, that oligothiophene trimer, disordered surface induced phase observed. Prospective structural models are tested refined various supercell constructions optimized by prior to refinements scattering data.