Molecular Assembly-Induced Charge Transfer for Programmable Functionalities

The donor-acceptor interface within molecular charge transfer (CT) solids plays a vital role in the hybridization of molecular orbitals to determine their carrier transport and electronic delocalization. In this study, we demonstrate molecular assembly-driven bilayer and crystalline solids, consisting of electron donor dibenzotetrathiafulvalene (DBTTF) and acceptor C₆₀, in which interfacial engineering-induced CT degree control is a key parameter for tuning its optical, electronic, and magnetic performance. Compared to the DBTTF/C₆₀ bilayer structure, the DBTTFC₆₀ cocrystalline solids show a stronger degree of charge transfer for broad CT absorption and a large dielectric constant. In addition, the DBTTFC₆₀ cocrystals exhibit distinct CT arrangement-driven anisotropic electron mobility and spin characteristics, which further enables the development of high-penetration and high-energy γ-ray photodetectors. The results presented in this paper provide a basis for the design and control of molecular charge transfer solids, which facilitates the integration of such materials into molecular electronics.