article published yes Woojung Lee author Shayan Louie author Austin M. Evans author Nicholas M. Orchanian author Ilana B. Stone author Boyuan Zhang author Yujing Wei author Xavier Roy author Colin Nuckolls author Latha Venkataraman author 9ebb78a5-cc0d-11ee-8322-fae086a32caf0000-0002-6957-6089 Coherent tunneling electron transport through molecular wires has been theoretically established as a temperature-independent process. Although several experimental studies have shown counter examples, robust models to describe this temperature dependence have not been thoroughly developed. Here, we demonstrate that dynamic molecular structures lead to temperature-dependent conductance within coherent tunneling regime. Using a custom-built variable-temperature scanning tunneling microscopy break-junction instrument, we find that oligo[n]phenylenes exhibit clear temperature-dependent conductance. Our calculations reveal that thermally activated dihedral rotations allow these molecular wires to have a higher probability of being in a planar conformation. As the tunneling occurs primarily through π-orbitals, enhanced coplanarization substantially increases the time-averaged tunneling probability. These calculations are consistent with the observation that more rotational pivot points in longer molecular wires leads to larger temperature-dependence on conductance. These findings reveal that molecular conductance within coherent and off-resonant electron transport regimes can be controlled by manipulating dynamic molecular structure. American Chemical Society2022 eng 1530-6984 1530-6992 3564006210.1021/acs.nanolett.2c01549 22124919-4924 yes Lee, Woojung, et al. “Increased Molecular Conductance in Oligo[n]Phenylene Wires by Thermally Enhanced Dihedral Planarization.” <i>Nano Letters</i>, vol. 22, no. 12, American Chemical Society, 2022, pp. 4919–24, doi:<a href="https://doi.org/10.1021/acs.nanolett.2c01549">10.1021/acs.nanolett.2c01549</a>. Lee, Woojung, Shayan Louie, Austin M. Evans, Nicholas M. Orchanian, Ilana B. Stone, Boyuan Zhang, Yujing Wei, Xavier Roy, Colin Nuckolls, and Latha Venkataraman. “Increased Molecular Conductance in Oligo[n]Phenylene Wires by Thermally Enhanced Dihedral Planarization.” <i>Nano Letters</i>. American Chemical Society, 2022. <a href="https://doi.org/10.1021/acs.nanolett.2c01549">https://doi.org/10.1021/acs.nanolett.2c01549</a>. Lee, W., Louie, S., Evans, A. M., Orchanian, N. M., Stone, I. B., Zhang, B., … Venkataraman, L. (2022). Increased molecular conductance in Oligo[n]phenylene wires by thermally enhanced dihedral planarization. <i>Nano Letters</i>. American Chemical Society. <a href="https://doi.org/10.1021/acs.nanolett.2c01549">https://doi.org/10.1021/acs.nanolett.2c01549</a> W. Lee <i>et al.</i>, “Increased molecular conductance in Oligo[n]phenylene wires by thermally enhanced dihedral planarization,” <i>Nano Letters</i>, vol. 22, no. 12. American Chemical Society, pp. 4919–4924, 2022. Lee W, Louie S, Evans AM, Orchanian NM, Stone IB, Zhang B, Wei Y, Roy X, Nuckolls C, Venkataraman L. 2022. Increased molecular conductance in Oligo[n]phenylene wires by thermally enhanced dihedral planarization. Nano Letters. 22(12), 4919–4924. W. Lee, S. Louie, A.M. Evans, N.M. Orchanian, I.B. Stone, B. Zhang, Y. Wei, X. Roy, C. Nuckolls, L. Venkataraman, Nano Letters 22 (2022) 4919–4924. Lee W, Louie S, Evans AM, et al. Increased molecular conductance in Oligo[n]phenylene wires by thermally enhanced dihedral planarization. <i>Nano Letters</i>. 2022;22(12):4919-4924. doi:<a href="https://doi.org/10.1021/acs.nanolett.2c01549">10.1021/acs.nanolett.2c01549</a> 178722024-09-06T13:06:35Z2024-12-10T09:40:39Z