ABSTRACT The performance of organic optoelectronic and energy-harvesting devices is largely determined by the molecular orientation and resultant permanent dipole moment, yet this property

is difficult to control during film preparation. Here, we demonstrate the active control of dipole direction—that is, vector direction and magnitude—in organic glassy films by physical

vapour deposition. An organic glassy film with metastable permanent dipole moment orientation can be obtained by utilizing the small surface free energy of a trifluoromethyl unit and

intramolecular permanent dipole moment induced by functional groups. The proposed molecular design rule could pave a way toward the formation of spontaneously polarized organic glassy films,

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subscriptions * Read our FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS BOOSTING SPONTANEOUS ORIENTATION POLARIZATION OF POLAR MOLECULES BASED ON FLUOROALKYL AND

PHTHALIMIDE UNITS Article Open access 29 October 2024 SPONTANEOUS ORIENTATION POLARIZATION DRIVEN BY DESIGNING MOLECULAR ASYMMETRY Article Open access 09 May 2025 PRECISE ORIENTATION CONTROL

OF A LIQUID CRYSTAL ORGANIC SEMICONDUCTOR VIA ANISOTROPIC SURFACE TREATMENT Article Open access 01 April 2022 DATA AVAILABILITY Source data are provided with this paper. Additional

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ACKNOWLEDGEMENTS The authors thank K. Kusuhara and N. Nakamura of Kyushu University for preparing chemicals and their thermal analysis. The authors also thank H. Fujimoto, H.-W. Mo and K.

Nagayoshi from i3-opera for their help with sample fabrication. This work was supported in part by the Programme for Building Regional Innovation Ecosystems of the Ministry of Education,

Culture, Sports, Science and Technology, Japan, the Hoso Bunka Foundation and the Japan Society for the Promotion of Science KAKENHI (grant no. JP21K19010). AUTHOR INFORMATION Author notes *

These authors contributed equally: Masaki Tanaka, Morgan Auffray. AUTHORS AND AFFILIATIONS * Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Nishi-ku,

Fukuoka, Japan Masaki Tanaka, Morgan Auffray, Hajime Nakanotani & Chihaya Adachi * Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Tokyo,

Japan Masaki Tanaka * International Institute for Carbon Neutral Energy Research (I2CNER), Kyushu University, Nishi-ku, Fukuoka, Japan Hajime Nakanotani & Chihaya Adachi Authors * Masaki

Tanaka View author publications You can also search for this author inPubMed Google Scholar * Morgan Auffray View author publications You can also search for this author inPubMed Google

Scholar * Hajime Nakanotani View author publications You can also search for this author inPubMed Google Scholar * Chihaya Adachi View author publications You can also search for this author

inPubMed Google Scholar CONTRIBUTIONS The project was conceived and designed by M.T. M.T. designed molecules and M.A. synthesized them. H.N. built the experimental set-up for surface

potential. M.T. prepared samples and measured their properties. M.T. and H.N. fabricated VPGs. M.T. and H.N. analysed data. All authors contributed to writing the paper and critically

commented on the project. CORRESPONDING AUTHORS Correspondence to Masaki Tanaka, Hajime Nakanotani or Chihaya Adachi. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing

interests. PEER REVIEW PEER REVIEW INFORMATION _Nature Materials_ thanks Wolfgang Bruetting, Hirohiko Fukagawa and the other, anonymous, reviewer(s) for their contribution to the peer

review of this work. ADDITIONAL INFORMATION PUBLISHER’S NOTE Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION Synthesis, Supplementary Figs. 1–24, Tables 1–3, Notes 1–3 and references. SOURCE DATA SOURCE DATA FIG. 3 Thickness dependence of surface

potential. SOURCE DATA FIG. 4 Device performance, including current density–voltage characteristics and output current profiles. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS

ARTICLE CITE THIS ARTICLE Tanaka, M., Auffray, M., Nakanotani, H. _et al._ Spontaneous formation of metastable orientation with well-organized permanent dipole moment in organic glassy

films. _Nat. Mater._ 21, 819–825 (2022). https://doi.org/10.1038/s41563-022-01265-7 Download citation * Received: 21 October 2021 * Accepted: 20 April 2022 * Published: 30 May 2022 * Issue

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