Single Molecule Conductance of Sequence-Defined Oligomers

Understanding electron transport through sequence-defined oligomers is a crucial step for designing new functional materials for energy storage. Recent advances in molecular electronics have brought us closer achieving the ultimate limits in miniaturization and spatial and functional control over electronic performance. Despite recent progress, our knowledge of molecular-scale electron transport is limited by the inability to explore the vast chemical sequence space using existing synthetic methods. In this work, we investigate the conductance properties of sequence-defined oligomers using a scanning tunneling microscope-break junction technique (STM-BJ). Starting from organic small molecules, we find that oxazole can serve as an effective anchor group to gold electrode. Using this approach, we systematically study the conductance pathways through pi-conjugated oxazole-containing molecules and oligomers. In particular, we characterize the electron transport properties of new classes of conjugated oligomers by varying the chemical identity of constituent monomers and the primary monomer sequence. In this way, our work provides the fundamental electron and charge transport information to inform future molecular electronics design.