{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T12:41:09Z","timestamp":1786452069946,"version":"build-2736575974"},"reference-count":61,"publisher":"AIP Publishing","issue":"6","funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS-2026-25481789"],"award-info":[{"award-number":["RS-2026-25481789"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,8,14]]},"abstract":"<jats:p>Many semiflexible filaments exhibit structural asymmetries that lead to a curved ground state (curvature in the absence of thermal fluctuations, external forces, or torques). This property is known as spontaneous curvature. Many semiflexible polymers can reversibly develop spontaneous curvature through internal conformational transitions or through transient interactions with their molecular environment. In this article, we show that such reversible spontaneous curvature, even in the absence of transitions in the value of the bending stiffness, provides a minimal mechanism for ensemble-dependent elasticity. We formulate an analytically tractable two-state modified wormlike-chain model in two dimensions, in which an uncurved state (without spontaneous curvature) competes with a curved state (possessing spontaneous curvature). The transition is controlled by an activation energy. Within the weak-bending approximation, we obtain the Gibbs and Helmholtz partition functions for a stretched filament with reversible constant (uniform along the backbone) or sinusoidal spontaneous curvature and for a grafted bistable filament driven either by an end torque or a bending force. Stretching or bending induces a crossover from spontaneous-curvature-dominated to entropic elasticity. We show how the elastic response differs in the two ensembles (Gibbs vs Helmholtz). In addition, we consider the case where the curved state is also characterized by a higher value of the bending stiffness. In that case, a reentrant transition is possible as we stretch the bistable filament.<\/jats:p>","DOI":"10.1063\/5.0349713","type":"journal-article","created":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T12:20:32Z","timestamp":1786450832000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["The elasticity of semiflexible polymers with reversible spontaneous curvature in two dimensions"],"prefix":"10.1063","volume":"165","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-0278-8117","authenticated-orcid":false,"given":"Donghyeon","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Physics, Kyungpook National University , 80 Daehakro, Bukgu, Daegu 41566,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9580-2644","authenticated-orcid":false,"given":"Panayotis","family":"Benetatos","sequence":"additional","affiliation":[{"name":"Department of Physics, Kyungpook National University , 80 Daehakro, Bukgu, Daegu 41566,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"317","published-online":{"date-parts":[[2026,8,11]]},"reference":[{"key":"2026081107481269300_c1","volume-title":"Statistical Mechanics of Polymer Chains","author":"Flory","year":"1989"},{"key":"2026081107481269300_c2","volume-title":"Thermodynamics and an Introduction to Thermostatistics","year":"1985"},{"key":"2026081107481269300_c3","doi-asserted-by":"publisher","first-page":"6183","DOI":"10.1039\/c0sm00488j","article-title":"Equivalence of statistical ensembles in stretching single flexible polymers","volume":"6","year":"2010","journal-title":"Soft Matter"},{"key":"2026081107481269300_c4","doi-asserted-by":"publisher","first-page":"491","DOI":"10.1038\/nmeth.1218","article-title":"Single-molecule force spectroscopy: Optical tweezers, magnetic tweezers and atomic force microscopy","volume":"5","year":"2008","journal-title":"Nat. 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