Abstract
The presence of multiple polarons, particularly at high doping levels, involves complex many-body interactions that substantially influence the electronic and transport properties of various materials. Determining the spatial distributions of coupled electronic and vibrational states is essential to understanding interacting polarons at a microscopic level but remains a challenge. Here we report the crystallization of electron polarons into quasi-one-dimensional polaron superlattices in highly n-doped single ethynylene-bonded polypentacenes. We employ integrated scanning tunnelling microscopy, atomic force microscopy and tip-enhanced Raman spectroscopy combined with first-principles density functional theory to correlate electronic, vibrational and structural information. The observed polaron superlattices exhibit different periodicities that depend on the doping levels. Their real-space polaron wavefunctions are determined by the intertwined electronic and vibrational periodic modulations associated with the periodic lattice distortions as resolved by atomic force microscopy. We can then identify the multiband charge-density-wave attributes of interacting polarons in these superlattices. Our findings provide microscopic insights in interacting polarons, which is important for the understanding of polaronic charge transport mechanisms in organic semiconductors.
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Data availability
The data required to reproduce the key findings of this work are publicly available via Zenodo at https://doi.org/10.5281/zenodo.16753004 (ref. 68). More detailed data are available from the corresponding authors on reasonable request.
References
Emin, D. Polarons (Cambridge Univ. Press, 2012).
Holstein, T. Studies of polaron motion: Part I. The molecular-crystal model. Ann. Phys. 8, 325–342 (1959).
Holstein, T. Studies of polaron motion: part II. The “small” polaron. Ann. Phys. 8, 343–389 (1959).
Fröhlich, H. Electrons in lattice fields. Adv. Phys. 3, 325–361 (1954).
Heeger, A. J. Semiconducting polymers: the third generation. Chem. Soc. Rev. 39, 2354–2371 (2010).
Brédas, J. L. & Street, G. B. Polarons, bipolarons, and solitons in conducting polymers. Acc. Chem. Res. 18, 309–315 (1985).
The Physics of Organic Superconductors and Conductors (Springer, 2008).
Franchini, C., Reticcioli, M., Setvin, M. & Diebold, U. Polarons in materials. Nat. Rev. Mater. 6, 560–586 (2021).
Buizza, L. R. V. & Herz, L. M. Polarons and charge localization in metal-halide semiconductors for photovoltaic and light-emitting devices. Adv. Mater. 33, 2007057 (2021).
Guo, X. & Facchetti, A. The journey of conducting polymers from discovery to application. Nat. Mater. 19, 922–928 (2020).
Fratini, S., Nikolka, M., Salleo, A., Schweicher, G. & Sirringhaus, H. Charge transport in high-mobility conjugated polymers and molecular semiconductors. Nat. Mater. 19, 491–502 (2020).
Liu, Y., Gao, S., Zhang, X., Xin, J. H. & Zhang, C. Probing the nature of charge carriers in one-dimensional conjugated polymers: a review of the theoretical models, experimental trends, and thermoelectric applications. J. Mater. Chem. C. 11, 12–47 (2023).
Salje, E. K. H. et al. (eds) Polarons and Bipolarons in High-Tc Superconductors and Related Materials (Cambridge Univ. Press, 1995).
Ramirez, A. P. Colossal magnetoresistance. J. Phys. Condens. Matter 9, 8171 (1997).
Koepsell, J. et al. Microscopic evolution of doped Mott insulators from polaronic metal to Fermi liquid. Science 374, 82–86 (2021).
Koschorreck, M. et al. Attractive and repulsive Fermi polarons in two dimensions. Nature 485, 619–622 (2012).
Alexandrov, A. S. Polarons in Advanced Materials (Springer, 2007).
Alexandrov, A. S. & Devreese, J. T. Advances in Polaron Physics (Springer, 2010).
Tang, H. et al. A solution-processed n-type conducting polymer with ultrahigh conductivity. Nature 611, 271–277 (2022).
Mertelj, T., Kabanov, V. V. & Mihailovic, D. Charged particles on a two-dimensional lattice subject to anisotropic Jahn–Teller interactions. Phys. Rev. Lett. 94, 147003 (2005).
Perfetti, L. et al. Spectroscopic indications of polaronic carriers in the quasi-one-dimensional conductor (TaSe4)2I. Phys. Rev. Lett. 87, 216404 (2001).
Sobota, J. A., He, Y. & Shen, Z.-X. Angle-resolved photoemission studies of quantum materials. Rev. Mod. Phys. 93, 025006 (2021).
Kruchinin, S. Multiband superconductors. Rev. Theor. Sci. 4, 165–178 (2016).
Mahan, G. D. Many-Particle Physics (Springer, 2013).
Sio, W. H., Verdi, C., Poncé, S. & Giustino, F. Polarons from first principles, without supercells. Phys. Rev. Lett. 122, 246403 (2019).
Sio, W. H., Verdi, C., Poncé, S. & Giustino, F. Ab initio theory of polarons: formalism and applications. Phys. Rev. B 99, 235139 (2019).
Sio, W. H. & Giustino, F. Polarons in two-dimensional atomic crystals. Nat. Phys. 19, 629–636 (2023).
Bhat, V., Callaway, C. P. & Risko, C. Computational approaches for organic semiconductors: from chemical and physical understanding to predicting new materials. Chem. Rev. 123, 7498–7547 (2023).
Anderson, M. et al. Displacement of polarons by vibrational modes in doped conjugated polymers. Phys. Rev. Mater. 1, 055604 (2017).
Reticcioli, M. et al. Polaron-driven surface reconstructions. Phys. Rev. X 7, 031053 (2017).
Guzelturk, B. et al. Visualization of dynamic polaronic strain fields in hybrid lead halide perovskites. Nat. Mater. 20, 618–623 (2021).
Gadelha, A. C. et al. Localization of lattice dynamics in low-angle twisted bilayer graphene. Nature 590, 405–409 (2021).
Bozin, E. S. et al. Crystallization of polarons through charge and spin ordering transitions in 1T-TaS2. Nat. Commun. 14, 7055 (2023).
Bombile, J. H., Janik, M. J. & Milner, S. T. Polaron formation mechanisms in conjugated polymers. Phys. Chem. Chem. Phys. 20, 317–331 (2018).
Xu, J. et al. Determining structural and chemical heterogeneities of surface species at the single-bond limit. Science 371, 818–822 (2021).
Zhu, X. et al. Revealing intramolecular isotope effects with chemical-bond precision. J. Am. Chem. Soc. 145, 13839–13845 (2023).
Cirera, B. et al. Tailoring topological order and π-conjugation to engineer quasi-metallic polymers. Nat. Nanotechnol. 15, 437–443 (2020).
González-Herrero, H. et al. Atomic scale control and visualization of topological quantum phase transition in π-conjugated polymers driven by their length. Adv. Mater. 33, e2104495 (2021).
Datar, A., Bar-Sadan, M. & Ramasubramaniam, A. Interactions between transition-metal surfaces and MoS2 monolayers: implications for hydrogen evolution and CO2 reduction reactions. J. Phys. Chem. C. 124, 20116–20124 (2020).
Kivelson, S. & Heeger, A. J. First-order transition to a metallic state in polyacetylene: a strong-coupling polaronic metal. Phys. Rev. Lett. 55, 308–311 (1985).
Stafström, S. et al. Polaron lattice in highly conducting polyaniline: theoretical and optical studies. Phys. Rev. Lett. 59, 1464–1467 (1987).
Pásztor, Á. et al. Multiband charge density wave exposed in a transition metal dichalcogenide. Nat. Commun. 12, 6037 (2021).
Barja, S. et al. Charge density wave order in 1D mirror twin boundaries of single-layer MoSe2. Nat. Phys. 12, 751–756 (2016).
Emin, D. Small polarons. Phys. Today 35, 34–40 (1982).
Yang, B. et al. Chemical enhancement and quenching in single-molecule tip-enhanced Raman spectroscopy. Angew. Chem. Int. Ed. 62, e202218799 (2023).
Zhang, C. et al. Chemical identification and bond control of π-skeletons in a coupling reaction. J. Am. Chem. Soc. 143, 9461–9467 (2021).
Hu, F. et al. Supermultiplexed optical imaging and barcoding with engineered polyynes. Nat. Methods 15, 194–200 (2018).
Köppel, H., Yarkony, D. R. & Barentzen, H. The Jahn-Teller effect: Fundamentals and implications for physics and chemistry (Springer, 2009).
Pouget, J. P. et al. X ray observation of 2kF and 4kF scatterings in tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ). Phys. Rev. Lett. 37, 437–440 (1976).
Schäfer, J. et al. Unusual spectral behavior of charge-density waves with imperfect nesting in a quasi-one-dimensional metal. Phys. Rev. Lett. 91, 066401 (2003).
Giessibl, F. J. The qPlus sensor, a powerful core for the atomic force microscope. Rev. Sci. Instrum. 90, 011101 (2019).
Kresse, G. & Furthmüller, J. Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set. Comput. Mater. Sci. 6, 15–50 (1996).
Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).
Grimme, S., Antony, J., Ehrlich, S. & Krieg, H. A consistent and accurate ab initio parametrization of density functional dispersion correction (DFT-D) for the 94 elements H-Pu. J. Chem. Phys. 132, 154104 (2010).
Blöchl, P. E. Projector augmented-wave method. Phys. Rev. B 50, 17953–17979 (1994).
Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Phys. Rev. B 59, 1758–1775 (1999).
Yakovkin, I. N. Quantum confinement in free Cu(111), Ag(111), and Au(111) layers and apparent splitting of surface bands. Surf. Sci. 691, 121501 (2020).
Bader, R. F. W. Atoms in molecules. Acc. Chem. Res. 18, 9–15 (1985).
Tang, W., Sanville, E. & Henkelman, G. A grid-based Bader analysis algorithm without lattice bias. J. Phys. Condens. Matter 21, 084204 (2009).
Tersoff, J. & Hamann, D. R. Theory and application for the scanning tunneling microscope. Phys. Rev. Lett. 50, 1998–2001 (1983).
Hapala, P. et al. Mechanism of high-resolution STM/AFM imaging with functionalized tips. Phys. Rev. B 90, 085421 (2014).
Peng, J. et al. Weakly perturbative imaging of interfacial water with submolecular resolution by atomic force microscopy. Nat. Commun. 9, 122 (2018).
Zhang, Y., Dong, Z.-C. & Aizpurua, J. Theoretical treatment of single-molecule scanning Raman picoscopy in strongly inhomogeneous near fields. J. Raman Spectrosc. 52, 296–309 (2021).
Hu, W. et al. Identifying the structure of 4-chlorophenyl isocyanide adsorbed on Au(111) and Pt(111) surfaces by first-principles simulations of Raman spectra. Phys. Chem. Chem. Phys. 19, 32389–32397 (2017).
Togo, A., Oba, F. & Tanaka, I. First-principles calculations of the ferroelastic transition between rutile-type and CaCl2-type SiO2 at high pressures. Phys. Rev. B 78, 134106 (2008).
Meena, R., Li, G. & Casula, M. Ground-state properties of the narrowest zigzag graphene nanoribbon from quantum Monte Carlo and comparison with density functional theory. J. Chem. Phys. 156, 084112 (2022).
Tesch, R. & Kowalski, P. M. Hubbard U parameters for transition metals from first principles. Phys. Rev. B 105, 195153 (2022).
Wu, Y. et al. Polaron superlattices in n-doped single conjugated polymers. Zenodo https://doi.org/10.5281/zenodo.16753004 (2025).
Acknowledgements
We thank Z. C. Dong for the helpful discussions on the TERS measurements. We acknowledge the NSRL (Hefei, China) for the provision of experimental facilities. X-ray photoelectron spectroscopy (XPS) measurements were performed at the Catalysis and Surface Science Endstation (BL11Ubeamline). We thank H. Ding for their assistance with using the BL11U photon beamline instrument. This work was supported by the Innovation Program for Quantum Science and Technology (grant number 2021ZD0303302), the National Natural Science Foundation of China (grant numbers 12074359 and 22425206), the Chinese Academy of Sciences (grant numbers XDB36020200 and PTYQ2024TD0011), the CAS Project for Young Scientists in Basic Research (grant number YSBR-054), the Anhui Initiative in Quantum Information Technologies (grant number AHY090000), the National Key Research and Development Program of China (grant number 2024YFA1208102), the New Cornerstone Science Foundation, and the robotic AI-Scientist platform of Chinese Academy of Sciences.
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C.M. and B.W. conceived the project. The on-surface synthesis and the STM/nc-AFM and TERS measurements were performed by Y.W., X.Z., Z.W. and R.Y. under the supervision of C.M., S.T., J.G.H. and B.W. Q.-S.D. synthesized and characterized the precursor molecule under the supervision of Y.-Z.T. The theoretical calculations of the EBPP chains were performed by B.L., Z.Z., B.Z. and H.S. under the supervision of Y.L. and J.Y. The vibrational calculation of the free pentacene molecule was performed by Y.Z. C.M. and B.W. wrote the paper with input from all authors.
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Extended data
Extended Data Fig. 1 On-surface synthesis of the pentacene polymers on different substrates after annealing at 430 K.
a, Chemical sketch of the precursor molecule 4BrPn. b,c, Large-area and high-resolution STM images of 3a-EBPP on the Ag(111) surface. In b, the directions of 3a-EBPP are indicated by white arrows. d, High-resolution STM image of 3a-EBPP on Ag(111) acquired with a Br-functionalized tip, showing an angle of approximately 14° between 3a-EBPP and the [1\(\bar{1}\)0] direction of the Ag(111) surface, as marked by the white lines. The DFT-optimized structural model is superimposed on the part of the STM image on the right of 3a-EBPP on Ag(111). e,f, Large-area and high-resolution STM images of 5a-EBPP on the Ag(100) surface, and g−i, 1a-EBPP on the Au(111) surface. In e, 5a-EBPP followed the two perpendicular high-symmetry directions on Ag(100). In g, 1a-EBPP formed domains randomly distributed on Au(111). In i, few polymer chains were confined by the herringbone reconstructions on Au(111). Imaging parameters: b, sample bias Vs = 1.0 V, tunnelling current It = 10 pA; c, Vs = 1.0 V, It = 100 pA; d, Vs = 0.2 V, It = 100 pA. e, Vs = 1.0 V, It = 10 pA; f, Vs = 0.25 V, It = 50 pA; g,h, Vs = 1.0 V, It = 50 pA; i, Vs = 1.0 V, It = 100 pA.
Extended Data Fig. 2 Analysis of the structural modulations in theoretically relaxed EBPPs by GGA+U.
a, Top and side views of the optimized structural model for freestanding 1a-EBPP in vacuum. The short axis direction and along the long axis direction of the pentacene moiety are marked. b−d, Side views of the optimized structural models (top panels) and the same side views with the z direction magnified by 5 times (bottom panels) for quasi-1a-EBPP on Au(111) (b), 3a-EBPP on Ag(111) (c), and 5a-EBPP on Ag(100) (d). The α (α1 and α2), β, and γ (γ1 and γ2) bonds and the numbers of C atoms along the backbone of the ethynylene-like bridges are marked in c and d. e, Heights of the marked C atoms in b−d with respect to the surface atoms of the metal substrates. The ethynylene-like (C≡C) bonds and benzene ring carbon atoms along the backbones are highlighted with thicker lines. f, Extracted tilting angles of the C≡C bonds (top panel), and the pentacene moieties along the short axis (middle panel) and along the long axis (bottom panel) of the pentacene moiety, with respect to the substrate surfaces. In the bottom panel, it is seen that the pentacene moieties at the two sides of the α bond present opposite tilting along the long axis of the pentacene moieties, in line with the observations in the nc-AFM images (Supplementary Fig. 3). In e and f, consistent results of overall larger tilting in the 5a-EBPP on Ag(100) than those in 3a-EBPP on Ag(111) are found. The connected lines in the lower panels just serve as a visual guide. In f, z-magnified structural models of 3a-EBPP and 5a-EBPP are shown as insets. The positive (+) and negative (−) values of the tilting angles from the substrate surface plane are schematically illustrated in the structural model of 5a-EBPP.
Extended Data Fig. 3 Measurements of the molecular skeleton and electronic states of 1a-EBPP on Au(111).
a, High-resolution STM image of 1a-EBPP on Au(111) acquired with a CO-functionalized tip. Imaging parameters: Vs = 1.0 V, It = 50 pA. b,c, Bond-resolved nc-AFM and current images of 1a-EBPP taken simultaneously at Vs = 10 mV. No end states were observed. The quality factor Q ≈ 5000. d, Profiles along the pairs of arrows marked lines in a−c, showing the 1a periodicity. e,f, Experimental and simulated nc-AFM images, and g, top and side views of the structural model of the end of 1a-EBPP on Au(111), showing the dangling C bonded to the Au surface. Here, the polymer along the \([11\overline{2}]\) direction, that is, the herringbone direction on Au(111), was adopted for the individual chain. h, Experimental and simulated STM topographic images obtained at the energies as indicated in the figures. i,j, dI/dV maps taken at 0.22 and −0.22 V (It = 50 pA, Vmod = 10 mV) and the corresponding simulated local density of state (LDOS) maps at edges of the valence band (VB) and conductance band (CB) in the quasi-1a-EBPP on Au(111). The chemical sketches of 1a-EBPP are superimposed.
Extended Data Fig. 4 Structural and electronic properties of 3a-EBPP on Ag(111).
a, Zoomed-in STM image of 3a-EBPP on Ag(111), showing two types of ends, the flat end (end-1) and the triangular end (end-2). Imaging parameters: Vs = 1.0 V, It = 30 pA. b,c, Nc-AFM and simultaneously obtained current images, taken with a CO-tip in the constant-height mode and within the same area as a. Imaging parameters: Vs = 5.0 mV. d, Zoomed-in experimental (left) and simulated (middle) nc-AFM images, and the structural model (right) of end-1, corresponding to the C−C−Ag configuration of the terminus. The Ag adatom is highlighted with blue in the structural model. e, Zoomed-in experimental (left) and simulated (middle) nc-AFM images, and the structural model (right) of end-2, corresponding to the C–CH3 configuration of the terminus. f,g, STM images, and h, dI/dV spectra taken at the marked sites 1−4 at ends and bare Ag(111) surface nearby, for two polymers with the end-1 and end-2, respectively. No clear end states around Fermi level were observed, in line with the featureless current image at the polymer ends. Imaging parameters: Vs = 1.0 V, It = 100 pA. Spectroscopy parameters: Vs = 0.5 V, It = 100 pA for curves 1 and 2; Vs = 0.6 V, It = 100 pA for curves 3, 4, and the spectrum taken on Ag(111). A lock-in amplifier with a sinusoidal peak-to-peak modulation of 10 mV at a frequency of 731 Hz was used.
Extended Data Fig. 5 Enveloped features in the observed superlattices.
a, Experimental STM images of 3a-EBPP on Ag(111), taken at −200 and 400 mV and 50 pA, respectively. b, Profile along the marked arrow pairs in the negative-bias STM in a. c, Simulated STM images of 3a-EBPP on Ag(111), obtained at −200 and 400 mV, respectively. d, Profile along the marked arrow pairs in the simulated negative-bias STM in c. e, Experimental STM images of 5a-EBPP on Ag(100), taken at −250 and 250 mV and 30 pA, respectively. f, Profile along the marked arrow pairs in the negative-bias STM in e. g, Simulated STM images of 5a-EBPP on Ag(100), obtained at −250 and 250 mV, respectively. h, Profile along the marked arrow pairs in the simulated negative-bias STM in g. The simulated STM images in c and g are obtained with Gaussian smoothing function by considering the tip convolution effect, processed with the standard deviation of 1.3 and 1.0 Å for positive and negative biases in c and 1.3 Å for both positive and negative biases in g, respectively.
Extended Data Fig. 6 Characterization of electronic states in 3a-EBPP on Ag(111).
a, dI/dV maps acquired with the indicated bias voltages, 20 pA for −50~50 mV and 50 pA for the other bias voltages, with 5 mV modulation for ±50 mV and 10 mV modulation for the other bias voltages. b, STM topographic image (−100 mV and 50 pA), within the same frame as in a. c, Normalized dI/dV spectra taken at the labelled sites in b, with the gray spectrum taken at the bare Ag(111) surface as a reference (Vs = 1 V, It = 50 pA, and modulation Vmod = 10 mV). The calculated DOS (black) by GGA+U with a Gaussian broadening of 10 meV is plotted at the bottom. The vertical red line indicates the EF, while the dashed black ones indicate the alignment between experimental and calculated orbitals. d, Simulated LDOS maps labelled with the main contributions at different energy levels from the X point or Γ point of the Brillion zone, with a tip height of 2−4 Å for various biases. The simulated LDOS maps at negative biases are obtained with Gaussian smoothing function by considering the tip convolution effect, processed with the standard deviation of 0.85 Å. e, Calculated band structures of 3a-EBPP on Ag(111), with different symbols correspondingly marking the contributions to the simulated LDOS maps in d, with visible splitting due to the hybridization with Ag(111) surface. f, Sketch of the polaron band structure of 3a-EBPP, with the band width derived from the experimental dI/dV maps that show the similar patterns. The different symbols give the estimated energies by the characterized CDWs in the dI/dV maps in a. In e,f, the orange and red shadows sketch the partially occupied and unoccupied polaron bands, with blue for the fully occupied band, considering their highly splitting feature.
Extended Data Fig. 7 Characterization of electronic states in 5a-EBPP on Ag(100).
a, dI/dV maps acquired with the indicated bias voltages and 30 pA, with 4 mV modulation for ±50 mV and 10 mV modulation for the other bias voltages. b, STM topographic image (−250 mV and 30 pA), within the same frame as in a. c, Normalized dI/dV spectra taken at the labelled sites in b, with the gray spectrum taken at the bare Ag(100) surface as a reference (1.0 V and 100 pA, and Vmod = 10 mV). The calculated DOS (black) calculated by GGA + U with a Gaussian broadening of 10 meV is plotted at the bottom. The vertical red line indicates the EF, while the dashed black ones indicate the alignment between experimental and calculated orbitals with empty or solid symbols with the same colour. d, Simulated LDOS maps labelled with the main contributions from the X point or Γ point of the Brillion zone, with a tip height of 2−4 Å for various biases. The simulated LDOS maps at negative biases are obtained with Gaussian smoothing function by considering the tip convolution effect, processed with the standard deviation of 1.0 Å. e, Calculated band structures of 5a-EBPP on Ag(100), with different symbols correspondingly marking the contributions to the simulated LDOS maps in d, with visible splitting due to the hybridization with Ag(100) surface. f, Sketch of the polaron band structure of 5a-EBPP, with the band width derived from the experimental dI/dV maps that show the similar patterns. The different symbols give the estimated energies by the characterized CDWs in the dI/dV maps in a. In e,f, the orange marks polaron bands, with other unoccupied bands in red, considering their highly splitting feature.
Extended Data Fig. 8 Simulations of the phonon band structures.
a−c, Simulated phonon bands corresponding to the experimentally observed 2050-cm−1 mode, and d−f, 858-cm−1 mode in 1a-EBPP (a,d), 3a-EBPP (b,e), and 5a-EBPP (c,f). In d−f, the dashed gray curves correspond to an almost degenerate mode of the 858-cm−1 mode, which is not distinguishable in our experiment. Threefold and fivefold split subbands are clearly observed in 3a-EBPP and 5a-EBPP, respectively, with clear gap opening at the Γ point and the Brillouin zone edges. The freestanding 1a-EBPP structure is relaxed under vacuum, while 3a-EBPP and 5a-EBPP are relaxed on Ag(111) and Ag(100) substrates. Then, the metal substrates are removed, and the corresponding amounts of transferred charge are added to the polymer chains to simulate the phonon band structures.
Extended Data Fig. 9 Contact-mode TERS measurements of 1a-EBPP on Au(111).
a, STM image of the 1a-EBPP polymer on Au(111). Imaging parameters: Vs = 0.1 V, It = 500 pA. b,d, Seven TERS spectra continuously taken with the contact-mode at the bridge bonds along the 1a-EBPP, showing the almost constant peak positions of 2002 and 860 cm−1. The spectra were taken at the labelled site in a. c,e, Waterfall plots for the TERS spectra from sites 1−7 as a function of tip height, showing the enhanced Raman peak intensities at approximately 2002 and 860 cm−1 during tip approaching. The tip height was with respect to the initial setpoint conditions of Vs = 0.1 V and It = 50 nA. Excitation light: 532 nm and 1.3 mW. The CCD spectrometer integration time was 20 s. Grating: 600 grooves/mm. Step distance: 10 pm.
Extended Data Fig. 10 Variations of the Raman peaks and widths of the out-of-plane C−H modes at different ethynylene-like bonds for 3a-EBPP and 5a-EBPP.
a,b, Plots of the measured Raman peaks and widths of the out-of-plane C−H modes at different ethynylene-like bonds for 3a-EBPP, and c,d, for 5a-EBPP, respectively. For 3a-EBPP and 5a-EBPP, the data are extracted from Fig. 3g and Supplementary Fig. 15f, respectively. The averaged spectra for C−H modes, acquired at sites near each ethynylene-like bond between neighbor pentacene moieties, are fitted separately by the Lorentzian function, shown as two sets of data for C−H modes close to each ethynylene-like site. The two data sets are plotted for the C−H modes obtained at the positions with respect to the polymer backbones, that is, positions 3 (a,c) and 7 (b,d) as labelled in Supplementary Fig. 15c,d. Error bars for the peak positions in Raman shift and for the peak width in FWHM are the standard errors obtained from the Lorentzian fitting of the Raman peaks, with centre of the error bar corresponding to the fitted peak position in each case. Spatial distributions of polaron densities |ψ|2, same as those in Fig. 5 in the main text, are overlaid for comparison.
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Supplementary Sections 1–12, Table 1 and Figs. 1–18.
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Wu, Y., Li, B., Zhu, X. et al. Polaron superlattices in n-doped single conjugated polymers. Nat. Nanotechnol. (2025). https://doi.org/10.1038/s41565-025-02019-7
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DOI: https://doi.org/10.1038/s41565-025-02019-7
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