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Chirality-induced relaxor properties in ferroelectric polymers


Relaxor ferroelectrics exhibit outstanding dielectric, electromechanical and electrocaloric properties, and are the materials of choice for acoustic sensors, solid-state coolers, transducers and actuators1,2,3,4. Despite more than five decades of intensive study, relaxor ferroelectrics remain one of the least understood material families in ferroelectric materials and condensed matter physics5,6,7,8,9,10,11,12,13,14. Here, by combining X-ray diffraction, atomic force microscope infrared spectroscopy and first-principles calculations, we reveal that the relaxor behaviour of ferroelectric polymers originates from conformational disorder, completely different from classic perovskite relaxors, which are typically characterized by chemical disorder. We show that chain chirality is essential to the formation of the disordered helix conformation arising from local distortions of gauche torsional angles, which consequently give rise to relaxor properties in polymers. This study not only sheds light on the fundamental mechanisms of relaxor ferroelectrics, but also offers guidance for the discovery of new ferroelectric relaxor organic materials for flexible, scalable and biocompatible sensor and energy applications.

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Fig. 1: Disordered helical chain structure driven by chirality in relaxor polymers.
Fig. 2: AFM-IR characterization of conformational disorder in relaxor ferroelectric polymers.
Fig. 3: Emergence of relaxor behaviour induced by chirality.
Fig. 4: Structural characterization by X-ray diffraction and Fourier-transform infrared spectroscopy (FTIR).
Fig. 5: Electrostrictive properties of PTrFE and PCTFE at room temperature.

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Data availability

The data that support the findings of this study are publicly available at Source data are provided with this paper.

Code availability

Quantum Espresso for DFT calculations can be downloaded from LAMMPS and ReaxFF for molecular dynamics or MM calculations can be found at Source data are provided with this paper.


  1. Cross, L. E., Jang, S. J., Newnham, R. E., Nomura, S. & Uchino, K. Large electrostrictive effects in relaxor ferroelectrics. Ferroelectrics 23, 187–192 (1980).

    Article  CAS  Google Scholar 

  2. Park, S. E. & Shrout, T. R. Ultrahigh strain and piezoelectric behavior in relaxor based ferroelectric single crystals. J. Appl. Phys. 82, 1804–1811 (1997).

    Article  CAS  Google Scholar 

  3. Zhang, Q. M., Bharti, V. & Zhao, X. Giant electrostriction and relaxor ferroelectric behavior in electron-irradiated poly(vinylidene fluoride-trifluoroethylene) copolymer. Science 280, 2101–2104 (1998).

    Article  CAS  Google Scholar 

  4. Kutnjak, Z., Petzelt, J. & Blinc, R. The giant electromechanical response in ferroelectric relaxors as a critical phenomenon. Nature 441, 956–959 (2006).

    Article  CAS  Google Scholar 

  5. Burns, G. & Dacol, F. H. Crystalline ferroelectrics with glassy polarization behaviour. Phys. Rev. B 28, 2527–2530 (1983).

    Article  CAS  Google Scholar 

  6. Westphal, V., Kleemann, W. & Glinchuk, M. D. Diffuse phase transitions and random-field-induced domain states of the ‘relaxor’ ferroelectric PbMg1/3Nb2/3O3. Phys. Rev. Lett. 68, 847–850 (1992).

    Article  CAS  Google Scholar 

  7. Tinte, S., Burton, B. P., Cockayne, E. & Waghmare, U. V. Origin of the relaxor state in Pb(BxB′1–x)O3 perovskites. Phys. Rev. Lett. 97, 137601 (2006).

    Article  Google Scholar 

  8. Dkhil, B. et al. Intermediate temperature scale T in lead-based relaxor systems. Phys. Rev. B 80, 064103 (2009).

    Article  Google Scholar 

  9. Ganesh, P. et al. Origin of diffuse scattering in relaxor ferroelectrics. Phys. Rev. B 81, 144102 (2010).

    Article  Google Scholar 

  10. Akbarzadeh, A. R., Prosandeev, S., Walter, E. J., Al-Barakaty, A. & Bellaiche, L. Finite-temperature properties of Ba(Zr,Ti)O3 relaxors from first principles. Phys. Rev. Lett. 108, 257601 (2012).

    Article  CAS  Google Scholar 

  11. Paściak, M., Welberry, T. R., Kulda, J., Kempa, M. & Hlinka, J. Polar nanoregions and diffuse scattering in the relaxor ferroelectric PbMg1/3Nb2/3O3. Phys. Rev. B 85, 224109 (2012).

    Article  Google Scholar 

  12. Bosak, A., Chernyshov, D., Vakhrushev, S. & Krisch, M. Diffuse scattering in relaxor ferroelectrics: true three-dimensional mapping, experimental artefacts and modelling. Acta Crystallogr. A 68, 117–123 (2012).

    Article  CAS  Google Scholar 

  13. Takenaka, H., Grinberg, I., Liu, S. & Rappe, A. M. Slush-like polar structures in single-crystal relaxors. Nature 546, 391–395 (2017).

    Article  CAS  Google Scholar 

  14. Krogstad, M. J. et al. The relation of local order to material properties in relaxor ferroelectrics. Nat. Mater. 17, 718–724 (2018).

    Article  CAS  Google Scholar 

  15. Yang, L. et al. Novel polymer ferroelectric behavior via crystal isomorphism and the nanoconfinement effect. Polymer 54, 1709–1728 (2013).

    Article  CAS  Google Scholar 

  16. Tsutsumi, N., Okumachi, K., Kinashi, K. & Wataru, S. Re-evaluation of the origin of relaxor ferroelectricity in vinylidene fluoride terpolymers: an approach using switching current measurements. Sci. Rep. 7, 15871 (2017).

    Article  Google Scholar 

  17. Pramanick, A. et al. Origin of dielectric relaxor behavior in PVDF-based copolymer and terpolymer films. AIP Adv. 8, 045204 (2018).

    Article  Google Scholar 

  18. Chu, B. et al. A dielectric polymer with high electric energy density and fast discharge speed. Science 313, 334–336 (2006).

    Article  CAS  Google Scholar 

  19. Neese, B. et al. Large electrocaloric effect in ferroelectric polymers near room temperature. Science 321, 821–823 (2008).

    Article  CAS  Google Scholar 

  20. Liu, Y. et al. Ferroelectric polymers exhibiting behaviour reminiscent of a morphotropic phase boundary. Nature 562, 96–100 (2018).

    Article  CAS  Google Scholar 

  21. Lovinger, A. J. Ferroelectric polymers. Science 220, 1115–1121 (1983).

    Article  CAS  Google Scholar 

  22. Bellet-Amalric, E. & Legrand, J. F. Crystalline structures and phase transition of the ferroelectric P(VDF-TrFE) copolymers, a neutron diffraction study. Eur. Phys. J. B 3, 225–236 (1998).

    Article  CAS  Google Scholar 

  23. Davis, G. T., Furukawa, T., Lovinger, A. J. & Broadhurst, M. G. Structural and dielectric investigation on the nature of the transition in a copolymer of vinylidene fluoride and trifluoroethylene (52/48 mol %). Macromolecules 15, 329–333 (1982).

    Article  CAS  Google Scholar 

  24. Lovinger, A. J. & Cais, R. E. Structure and morphology of poly(trifluoroethylene). Macromolecules 17, 1939–1945 (1984).

    Article  CAS  Google Scholar 

  25. Kolda, R. R. & Lando, J. B. The effect of hydrogen-fluorine defects on the conformational energy of polytrifluoroethylene chains. J. Macromol. Sci. B Phys. 11, 21–39 (1975).

    Article  Google Scholar 

  26. Bohlén, M. & Bolton, K. Conformational studies of poly(vinylidene fluoride), poly(trifluoroethylene) and poly(vinylidene fluoride-co-trifluoroethylene) using density functional theory. Phys. Chem. Chem. Phys. 16, 12929–12939 (2014).

    Article  Google Scholar 

  27. Kaufman, H. S. X-Ray examination of polychlorotrifluoroethylene. J. Am. Chem. Soc. 75, 1477–1478 (1953).

    Article  CAS  Google Scholar 

  28. Mencik, Z. Crystal structure of polychlorotrifluoroethylene. J. Polym. Sci. Polym. Phys. Ed. 11, 1585–1599 (1973).

    CAS  Google Scholar 

  29. Oka, Y. & Koizumi, N. Pyroelectricity in polytrifluoroethylene. Jpn. J. Appl. Phys. 22, L281–L283 (1983).

    Article  Google Scholar 

  30. Oka, Y., Koizumi, N. & Murata, Y. Ferroelectric order and phase transition in polytrifluoroethylene. J. Polym. Sci. B Polym. Phys. 24, 2059–2072 (1986).

    Article  CAS  Google Scholar 

  31. Gadinski, M. R., Li, Q., Zhang, G., Zhang, X. & Wang, Q. Understanding of relaxor ferroelectric behavior of poly(vinylidene fluoride–trifluoroethylene–chlorotrifluoroethylene) terpolymers. Macromolecules 48, 2731–2739 (2015).

    Article  CAS  Google Scholar 

  32. Gregorio, R. Jr Determination of the α, β, and γ crystalline phases of poly(vinylidene fluoride) films prepared at different conditions. J. Appl. Polym. Sci. 100, 3272–3279 (2006).

    Article  CAS  Google Scholar 

  33. Giannozzi, P. et al. Quantum Espresso: a modular and open-source software project for quantum simulations of materials. J. Phys. Condens. Matter 21, 395502 (2009).

    Article  Google Scholar 

  34. Vanderbilt, D. Soft self-consistent pseudopotentials in a generalized eigenvalue formalism. Phys. Rev. B 41, 7892–7895 (1990).

    Article  CAS  Google Scholar 

  35. Perdew, J. P., Kieron, B. & Matthias, E. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).

    Article  CAS  Google Scholar 

  36. Lee, K., Murray, É. D., Kong, L., Lundqvist, B. I. & Langreth, D. C. Higher-accuracy van der Waals density functional. Phys. Rev. B 82, 081101(R) (2010).

    Article  Google Scholar 

  37. Pack, J. D. & Monkhorst, H. J. “Special points for Brillouin-zone integrations”—a reply. Phys. Rev. B 16, 1748–1749 (1977).

    Article  Google Scholar 

  38. Plimpton, S. Fast parallel algorithms for short-range molecular dynamics. J. Comp. Phys. 117, 1–19 (1995).

    Article  CAS  Google Scholar 

  39. van Duin, A. C. T., Dasgupta, S., Lorant, F. & Goddard, W. A. ReaxFF: a reactive force field for hydrocarbons. J. Phys. Chem. A 105, 9396–9409 (2001).

    Article  Google Scholar 

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This research was funded by the US Air Force Office of Scientific Research through MURI FA9550-19-1-0008 (Q.W.) and the US Office of Naval Research (grant N000141912033, J.B.). The supercomputer time at the National Center for Supercomputing Applications (NSF OCI-0725070 and ACI-1238993) was provided by NSF grant ACI-1615114 (J.B.). Y.L. thanks T. Williams for technical assistance.

Author information

Authors and Affiliations



Y.L. and Q.W. designed the research; W.X. and Z.H. were responsible for the polymer synthesis and NMR measurements; Y.L. prepared the polymer films and collected X-ray diffraction data; Y.L. and A.H. performed FTIR, dielectric and electromechanical property measurements; and Y.L. collected the electrical conduction and AFM-IR data. B.Z., W.L. and J.B. performed the simulations and analysis. Y.L. and Q.W. wrote the manuscript with input from all authors. Q.W. supervised the research.

Corresponding author

Correspondence to Qing Wang.

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Extended data

Extended Data Fig. 1 XRD patterns of P(VDF-TrFE) copolymers.

θ-2θ scans of P(VDF-TrFE). The black dashed line indicates the (001) plane characteristic of long-range ferroelectricity while the light blue dash line indicates characteristic peaks originating from relaxor phases.

Extended Data Fig. 2 XRD patterns of ferroelectric in the paraelectric phase.

θ-2θ scans were obtained at 100 °C except for P(VDF-TrFE) 65/35 mol% at 130 °C. The dashed lines indicate characteristic peaks originating from paraelectric phases.

Extended Data Fig. 3

Intermolecular lattice spacing versus temperature in PTrFE.

Extended Data Fig. 4 Super cells of six different conformations used in DFT calculations to determine the stable crystalline PTrFE.

a, Left: The legend of elements. The chirality center carbon is colored orange in this figure. Right: schematic views of syndiotactic all-trans PTrFE chain from two directions, where the boxed -CHF-’s exhibit opposite chirality. b, Six-chain conformations in primitive unit cells in views from three directions as indicated in the rows. Column 1: axes; Column 2: iso/b; Column 3: iso/g; Column 4: iso/h; Column 5: syn/b; Column 6: syn/g; Column 7: syn/h. Iso and syn are abbreviations for isotactic and syndiotactic while h, b and g denote the (TG)3 (3/1-helical phase), the all trans (the β phase) and the T3GT3Ḡ (the γ phase) conformations, respectively. c, Supercells of six different conformations used in DFT calculations to determine the stable crystalline PTrFE in views from two different directions as indicated in the rows. Column 1: axes; Column 2: syn/b; Column 3: syn/g; Column 4: iso/h; Column 5: syn/b; Column 6: syn/g; Column 7: syn/h.

Extended Data Fig. 5 Supercells used in ReaxFF calculations for gauche distortion.

a, Top: the PTrFE supercell where all the 24 gauche torsional angles are constrained; Bottom left: the two finite chains used in DFT calculations where the two torsional angles in the black boxes are constrained. Bottom right pictures demonstrate how the gauche torsional angles (formed by the four carbon atoms in yellow) are changed in views from two directions. b, A summary of differences between the DFT calculations and the MM/ReaxFF calculations.

Extended Data Fig. 6 AFM-IR characterization of conformational disorder.

a and d, b and c, Simultaneously measured topographies (a,d) and AFM-IR chemical maps (b,e) exposed to a 1275 cm−1 and 1190 cm−1 laser light. The size of ae is 1 × 1 µm2. c and f, Local spectra of the positions marked in (a,d) and (b,e). The upper panels (a,b,c) P(VDF-CTFE) 90/10 mol%. The bottom panels (d,e,f) PCTFE.

Extended Data Fig. 7 Fit of dielectric data by the Vogel-Fulcher law.

a, PTrFE. b, PCTFE. c, P(VDF-CTFE) 90/10 mol%. d, P(VDF-CTFE) 80/20 mol%. The red line is a fit of the dielectric constant (solid black symbols) by the Vogel-Fulcher law. The fitting parameters can be found in Supplementary Table 2. Error bars represent standard deviations obtained from at least three measurements using different samples.

Extended Data Fig. 8 Ionic conductivity in PTrFE at different temperatures and frequencies.

a, Dielectric constant. b, dielectric loss. c, Conductivity. The gray region indicates the dominant region of ionic conductivity.

Extended Data Fig. 9 FTIR spectra.

a, From top to down: P(VDF-TrFE) 65/35 mol%, P(VDF-TrFE) 55/45 mol%, P(VDF-TrFE) 45/55 mol%, PTrFE, P(VDF-TrFE-CTFE) 61.8/30.4/7.8 mol%, P(VDF-TrFE-CFE) 61.5/30.3/8.2 mol%. b, From top to down: PVDF, P(VDF-CTFE) 90/10 mol%, and P(VDF- CTFE) 80/20 mol%.

Supplementary information

Supplementary Information

Supplementary Figs. 1–6, Tables 1–2 and refs. 39–47.

Source data

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Source data for Fig. 1b–d,f,g.

Source Data Fig. 2

Source data for Fig. 2g–i.

Source Data Fig. 3

Source data for Fig. 3a–d.

Source Data Fig. 4

Source data for Fig. 4a,b.

Source Data Fig. 5

Source data for Fig. 5a–f.

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Liu, Y., Zhang, B., Xu, W. et al. Chirality-induced relaxor properties in ferroelectric polymers. Nat. Mater. 19, 1169–1174 (2020).

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