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Disponible en 38 langues." > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-38" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">38 langues</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-af mw-list-item"><a href="https://af.wikipedia.org/wiki/Sigma-binding" title="Sigma-binding – afrikaans" lang="af" hreflang="af" data-title="Sigma-binding" data-language-autonym="Afrikaans" data-language-local-name="afrikaans" class="interlanguage-link-target"><span>Afrikaans</span></a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%B1%D8%A7%D8%A8%D8%B7%D8%A9_%D8%B3%D9%8A%D8%BA%D9%85%D8%A7" title="رابطة سيغما – arabe" lang="ar" hreflang="ar" data-title="رابطة سيغما" data-language-autonym="العربية" data-language-local-name="arabe" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Sigma_veza" title="Sigma veza – bosniaque" lang="bs" hreflang="bs" data-title="Sigma veza" data-language-autonym="Bosanski" data-language-local-name="bosniaque" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Enlla%C3%A7_sigma" title="Enllaç sigma – catalan" lang="ca" hreflang="ca" data-title="Enllaç sigma" data-language-autonym="Català" data-language-local-name="catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Vazba_sigma" title="Vazba sigma – tchèque" lang="cs" hreflang="cs" data-title="Vazba sigma" data-language-autonym="Čeština" data-language-local-name="tchèque" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Sigma-binding" title="Sigma-binding – danois" lang="da" hreflang="da" data-title="Sigma-binding" data-language-autonym="Dansk" data-language-local-name="danois" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de badge-Q70894304 mw-list-item" title=""><a href="https://de.wikipedia.org/wiki/%CE%A3-Bindung" title="Σ-Bindung – allemand" lang="de" hreflang="de" data-title="Σ-Bindung" data-language-autonym="Deutsch" data-language-local-name="allemand" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%94%CE%B5%CF%83%CE%BC%CF%8C%CF%82_%CF%83" title="Δεσμός σ – grec" lang="el" hreflang="el" data-title="Δεσμός σ" data-language-autonym="Ελληνικά" data-language-local-name="grec" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-en mw-list-item"><a href="https://en.wikipedia.org/wiki/Sigma_bond" title="Sigma bond – anglais" lang="en" hreflang="en" data-title="Sigma bond" data-language-autonym="English" data-language-local-name="anglais" class="interlanguage-link-target"><span>English</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Enlace_%CF%83" title="Enlace σ – espagnol" lang="es" hreflang="es" data-title="Enlace σ" data-language-autonym="Español" data-language-local-name="espagnol" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%BE%DB%8C%D9%88%D9%86%D8%AF_%D8%B3%DB%8C%DA%AF%D9%85%D8%A7" title="پیوند سیگما – persan" lang="fa" hreflang="fa" data-title="پیوند سیگما" data-language-autonym="فارسی" data-language-local-name="persan" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Sigmasidos" title="Sigmasidos – finnois" lang="fi" hreflang="fi" data-title="Sigmasidos" data-language-autonym="Suomi" data-language-local-name="finnois" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%A7%D7%A9%D7%A8_%D7%A1%D7%99%D7%92%D7%9E%D7%90" title="קשר סיגמא – hébreu" lang="he" hreflang="he" data-title="קשר סיגמא" data-language-autonym="עברית" data-language-local-name="hébreu" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%B8%E0%A4%BF%E0%A4%97%E0%A5%8D%E0%A4%AE%E0%A4%BE_%E0%A4%86%E0%A4%AC%E0%A4%A8%E0%A5%8D%E0%A4%A7" title="सिग्मा आबन्ध – hindi" lang="hi" hreflang="hi" data-title="सिग्मा आबन्ध" data-language-autonym="हिन्दी" data-language-local-name="hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Szigma-k%C3%B6t%C3%A9s" title="Szigma-kötés – hongrois" lang="hu" hreflang="hu" data-title="Szigma-kötés" data-language-autonym="Magyar" data-language-local-name="hongrois" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Ikatan_sigma" title="Ikatan sigma – indonésien" lang="id" hreflang="id" data-title="Ikatan sigma" data-language-autonym="Bahasa Indonesia" data-language-local-name="indonésien" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Legame_%CF%83" title="Legame σ – italien" lang="it" hreflang="it" data-title="Legame σ" data-language-autonym="Italiano" data-language-local-name="italien" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%CE%A3%E7%B5%90%E5%90%88" title="Σ結合 – japonais" lang="ja" hreflang="ja" data-title="Σ結合" data-language-autonym="日本語" data-language-local-name="japonais" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%8B%9C%EA%B7%B8%EB%A7%88_%EA%B2%B0%ED%95%A9" title="시그마 결합 – coréen" lang="ko" hreflang="ko" data-title="시그마 결합" data-language-autonym="한국어" data-language-local-name="coréen" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%A1%D0%B8%D0%B3%D0%BC%D0%B0-%D0%B2%D1%80%D1%81%D0%BA%D0%B0" title="Сигма-врска – macédonien" lang="mk" hreflang="mk" data-title="Сигма-врска" data-language-autonym="Македонски" data-language-local-name="macédonien" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-ml mw-list-item"><a href="https://ml.wikipedia.org/wiki/%E0%B4%B8%E0%B4%BF%E0%B4%97%E0%B5%8D%E0%B4%AE-%E0%B4%AC%E0%B4%A8%E0%B5%8D%E0%B4%A7%E0%B4%A8%E0%B4%82" title="സിഗ്മ-ബന്ധനം – malayalam" lang="ml" hreflang="ml" data-title="സിഗ്മ-ബന്ധനം" data-language-autonym="മലയാളം" data-language-local-name="malayalam" class="interlanguage-link-target"><span>മലയാളം</span></a></li><li class="interlanguage-link interwiki-mn mw-list-item"><a href="https://mn.wikipedia.org/wiki/%D0%A1%D0%B8%D0%B3%D0%BC%D0%B0_%D1%85%D0%BE%D0%BB%D0%B1%D0%BE%D0%BE%D1%81" title="Сигма холбоос – mongol" lang="mn" hreflang="mn" data-title="Сигма холбоос" data-language-autonym="Монгол" data-language-local-name="mongol" class="interlanguage-link-target"><span>Монгол</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Ikatan_sigma" title="Ikatan sigma – malais" lang="ms" hreflang="ms" data-title="Ikatan sigma" data-language-autonym="Bahasa Melayu" data-language-local-name="malais" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Sigma-binding" title="Sigma-binding – néerlandais" lang="nl" hreflang="nl" data-title="Sigma-binding" data-language-autonym="Nederlands" data-language-local-name="néerlandais" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Sigma-binding" title="Sigma-binding – norvégien bokmål" lang="nb" hreflang="nb" data-title="Sigma-binding" data-language-autonym="Norsk bokmål" data-language-local-name="norvégien bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Wi%C4%85zanie_sigma" title="Wiązanie sigma – polonais" lang="pl" hreflang="pl" data-title="Wiązanie sigma" data-language-autonym="Polski" data-language-local-name="polonais" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Liga%C3%A7%C3%A3o_sigma" title="Ligação sigma – portugais" lang="pt" hreflang="pt" data-title="Ligação sigma" data-language-autonym="Português" data-language-local-name="portugais" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Leg%C4%83tur%C4%83_sigma" title="Legătură sigma – roumain" lang="ro" hreflang="ro" data-title="Legătură sigma" data-language-autonym="Română" data-language-local-name="roumain" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%A1%D0%B8%D0%B3%D0%BC%D0%B0-%D1%81%D0%B2%D1%8F%D0%B7%D1%8C" title="Сигма-связь – russe" lang="ru" hreflang="ru" data-title="Сигма-связь" data-language-autonym="Русский" data-language-local-name="russe" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Sigma_veza" title="Sigma veza – serbo-croate" lang="sh" hreflang="sh" data-title="Sigma veza" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="serbo-croate" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Sigma_bond" title="Sigma bond – Simple English" lang="en-simple" hreflang="en-simple" data-title="Sigma bond" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Sigma_v%C3%A4zba" title="Sigma väzba – slovaque" lang="sk" hreflang="sk" data-title="Sigma väzba" data-language-autonym="Slovenčina" data-language-local-name="slovaque" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Vez_sigma" title="Vez sigma – slovène" lang="sl" hreflang="sl" data-title="Vez sigma" data-language-autonym="Slovenščina" data-language-local-name="slovène" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%A1%D0%B8%D0%B3%D0%BC%D0%B0_%D0%B2%D0%B5%D0%B7%D0%B0" title="Сигма веза – serbe" lang="sr" hreflang="sr" data-title="Сигма веза" data-language-autonym="Српски / srpski" data-language-local-name="serbe" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%A1%D0%B8%D0%B3%D0%BC%D0%B0-%D0%B7%D0%B2%27%D1%8F%D0%B7%D0%BE%D0%BA" title="Сигма-зв'язок – ukrainien" lang="uk" hreflang="uk" data-title="Сигма-зв'язок" data-language-autonym="Українська" data-language-local-name="ukrainien" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Li%C3%AAn_k%E1%BA%BFt_Sigma" title="Liên kết Sigma – vietnamien" lang="vi" hreflang="vi" data-title="Liên kết Sigma" data-language-autonym="Tiếng Việt" data-language-local-name="vietnamien" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%CE%A3%E9%94%AE" title="Σ键 – wu" lang="wuu" hreflang="wuu" data-title="Σ键" data-language-autonym="吴语" data-language-local-name="wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%CE%A3%E9%8D%B5" title="Σ鍵 – chinois" lang="zh" hreflang="zh" data-title="Σ鍵" data-language-autonym="中文" data-language-local-name="chinois" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a 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<td>————— </td></tr> <tr> <td valign="top" style="font-size:87%"><br /><br /><a href="/wiki/Orbitale_atomique" title="Orbitale atomique">Orbitales<br />atomiques</a> </td> <td colspan="2"><span typeof="mw:File"><a href="/wiki/Fichier:Electron_orbitals_crop.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a5/Electron_orbitals_crop.svg/250px-Electron_orbitals_crop.svg.png" decoding="async" width="250" height="265" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a5/Electron_orbitals_crop.svg/375px-Electron_orbitals_crop.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a5/Electron_orbitals_crop.svg/500px-Electron_orbitals_crop.svg.png 2x" data-file-width="450" data-file-height="477" /></a></span> </td></tr> <tr> <td>  </td> <td style="vertical-align:top; font-size:87%" width="144px"><span class="nowrap">Liaisons <span class="texhtml">σ</span></span> entre<br /><a href="/wiki/Orbitale_atomique" title="Orbitale atomique"><span class="nowrap">orbitales atomiques</span></a><br />s–s et p–p </td> <td style="vertical-align:top; font-size:87%"><a href="/wiki/Liaison_%CF%80" title="Liaison π"><span class="nowrap">Liaison <span class="texhtml">π</span></span></a><br />pour comparaison </td></tr> <tr style="font-size:6px; color:silver"> <td>——</td> <td>————————————————</td> <td>————— </td></tr> <tr> <td colspan="2" style="vertical-align:bottom; font-size:87%"><span typeof="mw:File"><a href="/wiki/Fichier:Molecular_orbital_of_hydrogen_fluoride.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/93/Molecular_orbital_of_hydrogen_fluoride.svg/144px-Molecular_orbital_of_hydrogen_fluoride.svg.png" decoding="async" width="144" height="114" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/93/Molecular_orbital_of_hydrogen_fluoride.svg/216px-Molecular_orbital_of_hydrogen_fluoride.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/93/Molecular_orbital_of_hydrogen_fluoride.svg/288px-Molecular_orbital_of_hydrogen_fluoride.svg.png 2x" data-file-width="241" data-file-height="190" /></a></span><br /><a href="/wiki/Fluorure_d%27hydrog%C3%A8ne" title="Fluorure d'hydrogène">Fluorure d'hydrogène</a> HF </td> <td style="vertical-align:bottom; font-size:87%"><span typeof="mw:File"><a href="/wiki/Fichier:Molecular_orbital_of_acetylene.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/5e/Molecular_orbital_of_acetylene.svg/128px-Molecular_orbital_of_acetylene.svg.png" decoding="async" width="128" height="79" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/5e/Molecular_orbital_of_acetylene.svg/192px-Molecular_orbital_of_acetylene.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/5e/Molecular_orbital_of_acetylene.svg/256px-Molecular_orbital_of_acetylene.svg.png 2x" data-file-width="365" data-file-height="225" /></a></span><br /><a href="/wiki/Ac%C3%A9tyl%C3%A8ne" title="Acétylène">Acétylène</a> <span class="nowrap">HC≡CH</span> </td></tr></tbody></table> <p>Une <b>liaison <span class="texhtml">σ</span></b> (prononcé <i><a href="/wiki/Sigma" title="Sigma">sigma</a></i>) est une <a href="/wiki/Liaison_chimique" title="Liaison chimique">liaison chimique</a> <a href="/wiki/Liaison_covalente" title="Liaison covalente">covalente</a> formée par le <a href="/wiki/Recouvrement_d%27orbitales" title="Recouvrement d'orbitales">recouvrement</a> axial de deux <a href="/wiki/Orbitale_atomique" title="Orbitale atomique">orbitales atomiques</a><sup id="cite_ref-978-0495390794_1-0" class="reference"><a href="#cite_note-978-0495390794-1"><span class="cite_crochet">[</span>1<span class="cite_crochet">]</span></a></sup>. Dans une <a href="/wiki/Mol%C3%A9cule_diatomique" title="Molécule diatomique">molécule diatomique</a> <a href="/wiki/Mol%C3%A9cule_homonucl%C3%A9aire" title="Molécule homonucléaire">homonucléaire</a>, la <a href="/wiki/Densit%C3%A9_%C3%A9lectronique" title="Densité électronique">densité électronique</a> est maximum le long de l'axe internucléaire, lequel n'est intersecté par aucun <a href="/wiki/Plan_nodal" title="Plan nodal">plan nodal</a>. De telles liaisons peuvent résulter du recouvrement d'orbitales <span class="nowrap">s + s</span>, <span class="nowrap">p<sub>z</sub> + p<sub>z</sub></span>, <span class="nowrap">s + p<sub>z</sub></span> ou <span class="nowrap">d<sub>z<sup>2</sup></sub> + d<sub>z<sup>2</sup></sub></span>, où z est l'axe internucléaire<sup id="cite_ref-978-0199270293_2-0" class="reference"><a href="#cite_note-978-0199270293-2"><span class="cite_crochet">[</span>2<span class="cite_crochet">]</span></a></sup>. Dans ces molécules, le concept de <span class="nowrap">liaison <span class="texhtml">σ</span></span> est équivalent à celui d'<a href="/wiki/Orbitale_mol%C3%A9culaire" title="Orbitale moléculaire">orbitale moléculaire</a> <span class="texhtml">σ</span>. Dans cette dernière, la densité électronique est distribuée selon une <a href="/wiki/Sym%C3%A9trie_circulaire" title="Symétrie circulaire">symétrie circulaire</a> autour de l'axe interatomique. Plus généralement, les <span class="nowrap">liaisons <span class="texhtml">σ</span></span> se forment par recouvrement axial d'orbitales atomiques, ce qui fait qu'une molécule d'<a href="/wiki/Alcane" title="Alcane">alcane</a> comme le <a href="/wiki/Propane" title="Propane">propane</a> C<sub>3</sub>H<sub>8</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub> est unie par dix <span class="nowrap">liaisons <span class="texhtml">σ</span></span>, à savoir huit liaisons <span class="nowrap"><a href="/wiki/Carbone" title="Carbone">C</a>–<a href="/wiki/Hydrog%C3%A8ne" title="Hydrogène">H</a></span> et deux liaisons <span class="nowrap"><a href="/wiki/Carbone" title="Carbone">C</a>–<a href="/wiki/Carbone" title="Carbone">C</a></span>. </p> <ul class="gallery mw-gallery-packed"> <li class="gallerybox" style="width: 272.66666666667px"> <div class="thumb" style="width: 270.66666666667px;"><span typeof="mw:File"><a href="/wiki/Fichier:Ligatio-covalens.svg" class="mw-file-description" title="Liaison σ entre deux atomes : localisation de la densité électronique."><img alt="Liaison σ entre deux atomes : localisation de la densité électronique." src="//upload.wikimedia.org/wikipedia/commons/thumb/2/21/Ligatio-covalens.svg/406px-Ligatio-covalens.svg.png" decoding="async" width="271" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/21/Ligatio-covalens.svg/609px-Ligatio-covalens.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/21/Ligatio-covalens.svg/812px-Ligatio-covalens.svg.png 2x" data-file-width="597" data-file-height="265" /></a></span></div> <div class="gallerytext"><div class="center">Liaison <span class="texhtml">σ</span> entre deux atomes : localisation de la <a href="/wiki/Densit%C3%A9_%C3%A9lectronique" title="Densité électronique">densité électronique</a>.</div></div> </li> </ul> <div class="mw-heading mw-heading2"><h2 id="Propriétés"><span id="Propri.C3.A9t.C3.A9s"></span>Propriétés</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Liaison_%CF%83&veaction=edit&section=1" title="Modifier la section : Propriétés" class="mw-editsection-visualeditor"><span>modifier</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Liaison_%CF%83&action=edit&section=1" title="Modifier le code source de la section : Propriétés"><span>modifier le code</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Les <span class="nowrap">liaisons <span class="texhtml">σ</span></span> sont les liaisons covalentes les plus fortes car le recouvrement axial est plus important que le recouvrement latéral d'une <a href="/wiki/Liaison_%CF%80" title="Liaison π"><span class="nowrap">liaison <span class="texhtml">π</span></span></a> ou d'une <a href="/wiki/Liaison_%CE%B4" title="Liaison δ"><span class="nowrap">liaison <span class="texhtml">δ</span></span></a>. Il ne peut exister qu'une seule <span class="nowrap">liaison <span class="texhtml">σ</span></span> entre deux atomes. Une <a href="/wiki/Liaison_simple" class="mw-redirect" title="Liaison simple">liaison simple</a> est généralement une <span class="nowrap">liaison <span class="texhtml">σ</span></span>, tandis qu'une <a href="/wiki/Liaison_double" title="Liaison double">double liaison</a> est généralement formée d'une <span class="nowrap">liaison <span class="texhtml">σ</span></span> et d'une <span class="nowrap">liaison <span class="texhtml">π</span></span> et qu'une <a href="/wiki/Liaison_triple" title="Liaison triple">triple liaison</a> est typiquement constituée d'une <span class="nowrap">liaison <span class="texhtml">σ</span></span> et de deux <span class="nowrap">liaisons <span class="texhtml">π</span></span>. L'<a href="/wiki/%C3%89nergie_de_dissociation_d%27une_liaison" title="Énergie de dissociation d'une liaison">énergie de dissociation</a> de la <a href="/wiki/Liaison_chimique" title="Liaison chimique">liaison</a> <span class="nowrap"><a href="/wiki/Carbone" title="Carbone">C</a>–<a href="/wiki/Carbone" title="Carbone">C</a></span> de l'<a href="/wiki/%C3%89thane" title="Éthane">éthane</a> H<sub>3</sub>C–CH<sub>3</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub> vaut <span title="3,596 402 eV ou 82 935,082 cal(th)/mol" style="cursor:help">347</span> à <span title="3,907 33 eV ou 90 105,262 cal(th)/mol" style="cursor:help">377</span> <abbr class="abbr" title="kilojoule par mole">kJ/mol</abbr>, tandis que celle de l'<a href="/wiki/%C3%89thyl%C3%A8ne" title="Éthylène">éthylène</a> H<sub>2</sub>C=CH<sub>2</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub> vaut <span title="7,358 632 eV ou 169 694,26 cal(th)/mol" style="cursor:help">710</span> <abbr class="abbr" title="kilojoule par mole">kJ/mol</abbr> et celle de l'<a href="/wiki/Ac%C3%A9tyl%C3%A8ne" title="Acétylène">acétylène</a> <span class="nowrap">HC≡CH</span> vaut <span title="9,949 699 eV ou 229 445,76 cal(th)/mol" style="cursor:help">960</span> <abbr class="abbr" title="kilojoule par mole">kJ/mol</abbr><sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite_crochet">[</span>3<span class="cite_crochet">]</span></a></sup>, illustrant qu'une <span class="nowrap">liaison <span class="texhtml">σ</span></span> est plus forte que des <span class="nowrap">liaisons <span class="texhtml">π</span></span>. </p><p>Les <a href="/wiki/Complexe_(chimie)" title="Complexe (chimie)">complexes</a> de <a href="/wiki/M%C3%A9tal_de_transition" title="Métal de transition">métaux de transition</a> qui présentent des <a href="/wiki/Liaison_multiple" class="mw-redirect" title="Liaison multiple">liaisons multiples</a>, comme les <a href="/wiki/Complexe_de_dihydrog%C3%A8ne" title="Complexe de dihydrogène">complexes de dihydrogène</a>, ont des <span class="nowrap">liaisons <span class="texhtml">σ</span></span> entre les atomes unis par des liaisons multiples. Ces <span class="nowrap">liaisons <span class="texhtml">σ</span></span> peuvent être complétées par d'autres interactions telles que des <a href="/wiki/R%C3%A9trocoordination_%CF%80" title="Rétrocoordination π"><span class="nowrap">rétrocoordinations <span class="texhtml">π</span></span></a>, comme dans le cas de W(CO)<sub>3</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub>(<a href="/w/index.php?title=Tricyclohexylphosphine&action=edit&redlink=1" class="new" title="Tricyclohexylphosphine (page inexistante)">PCy<sub>3</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub></a> <a href="https://en.wikipedia.org/wiki/Tricyclohexylphosphine" class="extiw" title="en:Tricyclohexylphosphine"><span class="indicateur-langue" title="Article en anglais : « Tricyclohexylphosphine »">(en)</span></a>)<sub>2</sub>(H<sub>2</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub>) ou encore des <a href="/wiki/Liaison_%CE%B4" title="Liaison δ"><span class="nowrap">liaisons <span class="texhtml">δ</span></span></a>, comme dans le cas de l'<a href="/wiki/Ac%C3%A9tate_de_chrome(II)" title="Acétate de chrome(II)">acétate de chrome(II)</a> Cr<sub>2</sub>(CH<sub>3</sub>CO<sub>2</sub>)<sub>4</sub>(H<sub>2</sub>O)<sub>2</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sup id="cite_ref-10.1021/ja0153417_4-0" class="reference"><a href="#cite_note-10.1021/ja0153417-4"><span class="cite_crochet">[</span>4<span class="cite_crochet">]</span></a></sup>. </p> <div class="mw-heading mw-heading2"><h2 id="Molécules_organiques"><span id="Mol.C3.A9cules_organiques"></span>Molécules organiques</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Liaison_%CF%83&veaction=edit&section=2" title="Modifier la section : Molécules organiques" class="mw-editsection-visualeditor"><span>modifier</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Liaison_%CF%83&action=edit&section=2" title="Modifier le code source de la section : Molécules organiques"><span>modifier le code</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Les <a href="/wiki/Mol%C3%A9cule" title="Molécule">molécules</a> <a href="/wiki/Compos%C3%A9_organique" title="Composé organique">organiques</a> présentent souvent des combinaisons de <span class="nowrap">liaisons <span class="texhtml">σ</span></span> et de <a href="/wiki/Liaison_%CF%80" title="Liaison π"><span class="nowrap">liaisons <span class="texhtml">π</span></span></a> dans des <a href="/wiki/Compos%C3%A9_chimique" title="Composé chimique">composés</a> qui peuvent être <a href="/wiki/Compos%C3%A9_cyclique" title="Composé cyclique">cycliques</a> ou <a href="/wiki/Compos%C3%A9_%C3%A0_cha%C3%AEne_ouverte" title="Composé à chaîne ouverte">à chaîne ouverte</a>. Le nombre <i>N</i><sub><span class="texhtml">σ</span></sub> de <span class="nowrap">liaisons <span class="texhtml">σ</span></span> de telles molécules peut être déduit par analogie avec la <a href="/wiki/Caract%C3%A9ristique_d%27Euler" title="Caractéristique d'Euler">caractéristique d'Euler</a> en considérant que les <a href="/wiki/Atome" title="Atome">atomes</a> sont des <a href="/wiki/Sommet_(g%C3%A9om%C3%A9trie)" title="Sommet (géométrie)">sommets</a>, les <span class="nowrap"><a href="/wiki/Liaison_chimique" title="Liaison chimique">liaisons</a> <span class="texhtml">σ</span></span> des <a href="/wiki/Ar%C3%AAte_(g%C3%A9om%C3%A9trie)" title="Arête (géométrie)">arêtes</a>, et les <a href="/wiki/Compos%C3%A9_cyclique" title="Composé cyclique">cycles</a> des <a href="/wiki/Face_(g%C3%A9om%C3%A9trie)" title="Face (géométrie)">faces</a> : </p> <dl><dd><i>N</i><sub><span class="texhtml">σ</span></sub> = <i>N</i><sub><a href="/wiki/Atome" title="Atome">atomes</a></sub> + <i>N</i><sub><a href="/wiki/Compos%C3%A9_cyclique" title="Composé cyclique">cycles</a></sub> – 1.</dd></dl> <p>Cette formule fonctionne bien pour les molécules qui peuvent être représentées de manière bidimensionnelle : le <a href="/wiki/M%C3%A9thane" title="Méthane">méthane</a> CH<sub>4</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub> contient ainsi quatre <span class="nowrap">liaisons <span class="texhtml">σ</span></span>, l'<a href="/wiki/%C3%89thane" title="Éthane">éthane</a> C<sub>2</sub>H<sub>6</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub> en contient sept (six liaisons <span class="nowrap"><a href="/wiki/Carbone" title="Carbone">C</a>–<a href="/wiki/Hydrog%C3%A8ne" title="Hydrogène">H</a></span> et une liaison <span class="nowrap"><a href="/wiki/Carbone" title="Carbone">C</a>–<a href="/wiki/Carbone" title="Carbone">C</a></span>), l'<span class="page_h"><a href="/wiki/Hexane" class="mw-disambig" title="Hexane">hexane</a></span> C<sub>6</sub>H<sub>14</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub> en contient 19, le <a href="/wiki/Cyclohexane" title="Cyclohexane">cyclohexane</a> C<sub>6</sub>H<sub>12</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub> en contient 18, le <a href="/wiki/Benz%C3%A8ne" title="Benzène">benzène</a> C<sub>6</sub>H<sub>6</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub> en contient 12, le <a href="/wiki/Naphtal%C3%A8ne" title="Naphtalène">naphtalène</a> C<sub>10</sub>H<sub>8</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub> en contient 19, <abbr class="abbr" title="et cetera">etc.</abbr> Dans certains cas, il peut s'agir d'une <span class="nowrap">liaison <span class="texhtml">σ</span></span> virtuelle, comme pour le <a href="/wiki/Carbone_diatomique" title="Carbone diatomique">carbone diatomique</a> C<sub>2</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub> uni seulement par deux <span class="nowrap">liaisons <span class="texhtml">π</span></span> mais qui contient également une <span class="nowrap">liaison <span class="texhtml">σ</span></span> annulée par une <a href="/wiki/Orbitale_antiliante" title="Orbitale antiliante"><span class="nowrap">orbitale <span class="texhtml">σ*</span></span> antiliante</a>. </p><p>Cette formule atteint ses limites avec des composés plus complexes dont la géométrie ne peut être représentée simplement dans un plan, ce qui modifie la caractéristique d'Euler. C'est par exemple le cas du <a href="/wiki/Buckminsterfuller%C3%A8ne" title="Buckminsterfullerène">buckminsterfullerène</a> C<sub>60</sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub><sub></sub>, qui contient 60 atomes, 32 cycles et 90 <abbr class="abbr" title="liaisons σ"><span class="nowrap">liaisons <span class="texhtml">σ</span></span></abbr> ; la formule donnerait, quant à elle, <span class="nowrap">60 + 32 – 1 = 91 liaisons <span class="texhtml">σ</span></span>. </p> <div class="mw-heading mw-heading2"><h2 id="Notes_et_références"><span id="Notes_et_r.C3.A9f.C3.A9rences"></span>Notes et références</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Liaison_%CF%83&veaction=edit&section=3" title="Modifier la section : Notes et références" class="mw-editsection-visualeditor"><span>modifier</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Liaison_%CF%83&action=edit&section=3" title="Modifier le code source de la section : Notes et références"><span>modifier le code</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="references-small decimal" style=""><div class="mw-references-wrap"><ol class="references"> <li id="cite_note-978-0495390794-1"><span class="mw-cite-backlink noprint"><a href="#cite_ref-978-0495390794_1-0">↑</a> </span><span class="reference-text"><abbr class="abbr indicateur-langue" title="Langue : anglais">(en)</abbr> John Moore, Conrad L. Stanitski et Peter C. Jurs, <i>Principles of Chemistry: The Molecular Science</i>, 2009. <small style="line-height:1em;">(<a href="/wiki/International_Standard_Book_Number" title="International Standard Book Number">ISBN</a> <a href="/wiki/Sp%C3%A9cial:Ouvrages_de_r%C3%A9f%C3%A9rence/978-0495390794" title="Spécial:Ouvrages de référence/978-0495390794"><span class="nowrap">978-0495390794</span></a>)</small></span> </li> <li id="cite_note-978-0199270293-2"><span class="mw-cite-backlink noprint"><a href="#cite_ref-978-0199270293_2-0">↑</a> </span><span class="reference-text"><abbr class="abbr indicateur-langue" title="Langue : anglais">(en)</abbr> Jonathan Clayden, Nick Greeves et Stuart Warren, <i>Organic Chemistry</i>, <abbr class="abbr" title="Deuxième">2<sup>e</sup></abbr>  <abbr class="abbr" title="édition">éd.</abbr>, OUP Oxford, 2012, <abbr class="abbr" title="pages">p.</abbr> <span class="nowrap">101-136</span>. <small style="line-height:1em;">(<a href="/wiki/International_Standard_Book_Number" title="International Standard Book Number">ISBN</a> <a href="/wiki/Sp%C3%A9cial:Ouvrages_de_r%C3%A9f%C3%A9rence/978-0199270293" title="Spécial:Ouvrages de référence/978-0199270293"><span class="nowrap">978-0199270293</span></a>)</small></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink noprint"><a href="#cite_ref-3">↑</a> </span><span class="reference-text"> <span class="ouvrage" id="Bergman_et_A._Streitwieser2018"><span class="ouvrage" id="R._G._Bergman_et_A._Streitwieser2018"><abbr class="abbr indicateur-langue" title="Langue : anglais">(en)</abbr> R. G. Bergman et A. Streitwieser, « <a rel="nofollow" class="external text" href="https://archive.org/details/bergman-r.-g.-streitwieser-a.-table-of-organic-bond-dissociation-energies-2018/mode/1up"><cite style="font-style:normal;" lang="en">Bond Dissociation Energies (DH<span class="unicode" style="white-space:nowrap; display:inline-block; margin-bottom:-0.3em; vertical-align:-0.4em; line-height:1em; font-size:80%; text-align:left;">0<br />298</span>, kcal mol<sup>-1</sup>) for A-B Bonds</cite></a> » <abbr class="abbr indicateur-format format-pdf" title="Document au format Portable Document Format (PDF) d'Adobe">[PDF]</abbr>, <a href="/wiki/Universit%C3%A9_de_Californie_%C3%A0_Berkeley" title="Université de Californie à Berkeley">Université de Californie à Berkeley</a>, <time class="nowrap" datetime="2018-09-19" data-sort-value="2018-09-19">19 septembre 2018</time> <small style="line-height:1em;">(consulté le <time class="nowrap" datetime="2022-02-10" data-sort-value="2022-02-10">10 février 2022</time>)</small></span></span>.</span> </li> <li id="cite_note-10.1021/ja0153417-4"><span class="mw-cite-backlink noprint"><a href="#cite_ref-10.1021/ja0153417_4-0">↑</a> </span><span class="reference-text"> <span class="ouvrage" id="Ray_L._Sweany2002"><abbr class="abbr indicateur-langue" title="Langue : anglais">(en)</abbr> <span class="nom_auteur">Ray L. Sweany</span>, « <cite style="font-style:normal" lang="en">Metal Dihydrogen and σ-Bond Complexes: Structure, Theory, and Reactivity By Gregory J. Kubas, Los Alamos National Laboratory, Kluwer Academic/Plenum Publishers: New York. 2001</cite> », <i><span class="lang-en" lang="en">Journal of the American Chemical Society</span></i>, <abbr class="abbr" title="volume">vol.</abbr> 124, <abbr class="abbr" title="numéro">n<sup>o</sup></abbr> 14,‎ <time class="nowrap" datetime="2002-02-07" data-sort-value="2002-02-07">7 février 2002</time>, <abbr class="abbr" title="pages">p.</abbr> <span class="nowrap">3799-3800</span> <small style="line-height:1em;">(<a href="/wiki/Digital_Object_Identifier" title="Digital Object Identifier">DOI</a> <span class="plainlinks noarchive nowrap"><a rel="nofollow" class="external text" href="https://dx.doi.org/10.1021/ja0153417">10.1021/ja0153417</a></span>, <a rel="nofollow" class="external text" href="https://pubs.acs.org/doi/10.1021/ja0153417">lire en ligne</a>)</small><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Metal+Dihydrogen+and+%CF%83-Bond+Complexes%3A%E2%80%89+Structure%2C+Theory%2C+and+Reactivity+By+Gregory+J.+Kubas%2C+Los+Alamos+National+Laboratory%2C+Kluwer+Academic%2FPlenum+Publishers%3A%E2%80%89+New+York.+2001&rft.jtitle=Journal+of+the+American+Chemical+Society&rft.issue=14&rft.aulast=Ray+L.+Sweany&rft.date=2002-02-07&rft.volume=124&rft.pages=3799-3800&rft_id=info%3Adoi%2F10.1021%2Fja0153417&rfr_id=info%3Asid%2Ffr.wikipedia.org%3ALiaison+%CF%83"></span></span></span> </li> </ol></div> </div> <div class="navbox-container" style="clear:both;"> <table class="navbox collapsible noprint autocollapse" style=""> <tbody><tr><th class="navbox-title" colspan="2" style=""><div style="float:left; width:6em; text-align:left"><div class="noprint plainlinks nowrap tnavbar" style="padding:0; font-size:xx-small; color:var(--color-emphasized, #000000);"><a href="/wiki/Mod%C3%A8le:Palette_Liaisons_chimiques" title="Modèle:Palette Liaisons chimiques"><abbr class="abbr" title="Voir ce modèle.">v</abbr></a> · <a class="external text" href="https://fr.wikipedia.org/w/index.php?title=Mod%C3%A8le:Palette_Liaisons_chimiques&action=edit"><abbr class="abbr" title="Modifier ce modèle. Merci de prévisualiser avant de sauvegarder.">m</abbr></a></div></div><div style="font-size:110%"><a href="/wiki/Liaison_chimique" title="Liaison chimique">Liaisons chimiques</a></div></th> </tr> <tr> <th class="navbox-group" style="width:100px"><a href="/wiki/Force_intramol%C3%A9culaire" title="Force intramoléculaire">Intramoléculaire<br />(« forte »)</a></th> <td class="navbox-list" style=""><table class="navbox-subgroup" style=""> <tbody><tr> <th class="navbox-group" style="width:130px"><a href="/wiki/Liaison_covalente" title="Liaison covalente">Liaisons covalentes</a></th> <td class="navbox-list navbox-even" style=";background:#ECECFF; text-align:left;"><div class="liste-horizontale"> <ul><li><a class="mw-selflink selflink">Liaison <span class="texhtml">σ</span></a></li> <li><a href="/wiki/Liaison_%CF%80" title="Liaison π">Liaison <span class="texhtml">π</span></a></li> <li><a href="/wiki/Liaison_%CE%B4" title="Liaison δ">Liaison <span class="texhtml">δ</span></a></li> <li><a href="/wiki/Liaison_%CF%86" title="Liaison φ">Liaison <span class="texhtml">φ</span></a></li> <li><a href="/wiki/Liaison_double" title="Liaison double">Liaison double</a></li> <li><a href="/wiki/Liaison_triple" title="Liaison triple">Liaison triple</a></li> <li><a href="/wiki/Liaison_quadruple" title="Liaison quadruple">Liaison quadruple</a></li> <li><a href="/wiki/Liaison_quintuple" title="Liaison quintuple">Liaison quintuple</a></li> <li><a href="/wiki/Liaison_sextuple" title="Liaison sextuple">Liaison sextuple</a></li> <li><a href="/wiki/Liaison_%C3%A0_trois_centres_et_deux_%C3%A9lectrons" title="Liaison à trois centres et deux électrons">3c–2e</a></li> <li><a href="/wiki/Liaison_%C3%A0_trois_centres_et_quatre_%C3%A9lectrons" title="Liaison à trois centres et quatre électrons">3c–4e</a></li> <li><a href="/wiki/Liaison_%C3%A0_quatre_centres_et_deux_%C3%A9lectrons" title="Liaison à quatre centres et deux électrons">4c–2e</a></li> <li><a href="/wiki/Interaction_agostique" title="Interaction agostique">Liaison agostique</a></li> <li><a href="/wiki/Liaison_banane" title="Liaison banane">Liaison banane</a></li> <li><a href="/wiki/Liaison_covalente_de_coordination" title="Liaison covalente de coordination">Liaison covalente de coordination</a></li> <li><a href="/wiki/R%C3%A9trocoordination_%CF%80" title="Rétrocoordination π">Rétro-donation</a></li> <li><a href="/wiki/Syst%C3%A8me_conjugu%C3%A9" title="Système conjugué">Conjugaison</a></li> <li><a href="/wiki/Hyperconjugaison" title="Hyperconjugaison">Hyperconjugaison</a></li> <li><a href="/wiki/Aromaticit%C3%A9" title="Aromaticité">Aromaticité</a></li> <li><a href="/wiki/Hapticit%C3%A9" title="Hapticité">Hapticité</a></li> <li><a href="/wiki/Orbitale_antiliante" title="Orbitale antiliante">Orbitale antiliante</a></li> <li><a href="/wiki/Pont_disulfure" title="Pont disulfure">Pont disulfure</a></li></ul> </div></td> </tr> <tr> <th class="navbox-group" style="width:130px"><a href="/wiki/Liaison_ionique" title="Liaison ionique">Liaisons ioniques</a></th> <td class="navbox-list" style=";background:#ECECFF; text-align:left;"><div class="liste-horizontale"> <ul><li><a href="/w/index.php?title=Interaction_cation%E2%80%93%CF%80&action=edit&redlink=1" class="new" title="Interaction cation–π (page inexistante)">Liaison cation–π</a> <a href="https://en.wikipedia.org/wiki/Cation%E2%80%93pi_interaction" class="extiw" title="en:Cation–pi interaction"><span class="indicateur-langue" title="Article en anglais : « Cation–pi interaction »">(en)</span></a></li> <li><a href="/w/index.php?title=Pont_salin_(prot%C3%A9ine_et_supramol%C3%A9cule)&action=edit&redlink=1" class="new" title="Pont salin (protéine et supramolécule) (page inexistante)">Pont salin</a> <a href="https://en.wikipedia.org/wiki/Salt_bridge_(protein_and_supramolecular)" class="extiw" title="en:Salt bridge (protein and supramolecular)"><span class="indicateur-langue" title="Article en anglais : « Salt bridge (protein and supramolecular) »">(en)</span></a></li></ul> </div></td> </tr> <tr> <th class="navbox-group" style="width:130px"><a href="/wiki/Liaison_m%C3%A9tallique" title="Liaison métallique">Liaisons métalliques</a></th> <td class="navbox-list navbox-even" style=";background:#ECECFF; text-align:left;"><div class="liste-horizontale"> <ul><li><a href="/wiki/Aromaticit%C3%A9_m%C3%A9tallique" title="Aromaticité métallique">Aromaticité métallique</a></li></ul> </div></td> </tr> </tbody></table></td> </tr> <tr> <th class="navbox-group" style="width:100px"><a href="/wiki/Force_intermol%C3%A9culaire" title="Force intermoléculaire">Intermoléculaire<br />(« faible »)</a></th> <td class="navbox-list" style=""><table class="navbox-subgroup" style=""> <tbody><tr> <th class="navbox-group" style="width:130px"><a href="/wiki/Liaison_hydrog%C3%A8ne" title="Liaison hydrogène">Liaison hydrogène</a></th> <td class="navbox-list navbox-even" style=";background:#ECECFF; text-align:left;"><div class="liste-horizontale"> <ul><li><a href="/wiki/Liaison_dihydrog%C3%A8ne" title="Liaison dihydrogène">Liaison dihydrogène</a></li> <li><a href="/w/index.php?title=Complexe_dihydrog%C3%A8ne&action=edit&redlink=1" class="new" title="Complexe dihydrogène (page inexistante)">Complexe dihydrogène</a></li> <li><a href="/w/index.php?title=Liaison_hydrog%C3%A8ne_%C3%A0_faible_barri%C3%A8re&action=edit&redlink=1" class="new" title="Liaison hydrogène à faible barrière (page inexistante)">Liaison hydrogène à faible barrière</a> <a href="https://en.wikipedia.org/wiki/Low-barrier_hydrogen_bond" class="extiw" title="en:Low-barrier hydrogen bond"><span class="indicateur-langue" title="Article en anglais : « Low-barrier hydrogen bond »">(en)</span></a></li> <li><a href="/w/index.php?title=Liaison_hydrog%C3%A8ne_sym%C3%A9trique&action=edit&redlink=1" class="new" title="Liaison hydrogène symétrique (page inexistante)">Liaison hydrogène symétrique</a> <a href="https://en.wikipedia.org/wiki/Symmetric_hydrogen_bond" class="extiw" title="en:Symmetric hydrogen bond"><span class="indicateur-langue" title="Article en anglais : « Symmetric hydrogen bond »">(en)</span></a></li></ul> </div></td> </tr> <tr> <th class="navbox-group" style="width:130px">Autre <a href="/wiki/Interaction_non_covalente" title="Interaction non covalente">non covalente</a></th> <td class="navbox-list" style=";background:#ECECFF; text-align:left;"><div class="liste-horizontale"> <ul><li><a href="/wiki/Force_de_van_der_Waals" title="Force de van der Waals">Force de van der Waals</a> <ul><li><a href="/wiki/Forces_de_London" title="Forces de London">Force de London</a></li> <li><a href="/wiki/Forces_de_Debye" title="Forces de Debye">Force de Debye</a></li> <li><a href="/wiki/Forces_de_Keesom" title="Forces de Keesom">Force de Keesom</a></li></ul></li> <li><a href="/w/index.php?title=Liaison_m%C3%A9canique_(chimie)&action=edit&redlink=1" class="new" title="Liaison mécanique (chimie) (page inexistante)">Liaison mécanique</a> <a href="https://en.wikipedia.org/wiki/Mechanically_interlocked_molecular_architectures" class="extiw" title="en:Mechanically interlocked molecular architectures"><span class="indicateur-langue" title="Article en anglais : « Mechanically interlocked molecular architectures »">(en)</span></a></li> <li><a href="/wiki/Liaison_halog%C3%A8ne" title="Liaison halogène">Liaison halogène</a></li> <li><a href="/w/index.php?title=Aurophilie&action=edit&redlink=1" class="new" title="Aurophilie (page inexistante)">Aurophilie</a> <a href="https://en.wikipedia.org/wiki/Aurophilicity" class="extiw" title="en:Aurophilicity"><span class="indicateur-langue" title="Article en anglais : « Aurophilicity »">(en)</span></a></li> <li><a href="/wiki/Intercalation_(chimie)" title="Intercalation (chimie)">Intercalation</a></li> <li><a href="/wiki/Empilement_Pi" title="Empilement Pi">Empilage</a></li> <li><a href="/wiki/Force_entropique" title="Force entropique">Force entropique</a></li> <li><a href="/wiki/Polarit%C3%A9_(chimie)" title="Polarité (chimie)">Polarité</a></li></ul> </div></td> </tr> </tbody></table></td> </tr> <tr> <th class="navbox-group" style="width:100px"><a href="/wiki/Clivage_(chimie)" title="Clivage (chimie)">Clivage</a><br /></th> <td class="navbox-list navbox-even" style=""><div class="liste-horizontale"> <ul><li><a href="/wiki/H%C3%A9t%C3%A9rolyse" title="Hétérolyse">Hétérolyse</a></li> <li><a href="/wiki/Homolyse" title="Homolyse">Homolyse</a></li></ul> </div></td> </tr> </tbody></table> </div> <ul id="bandeau-portail" class="bandeau-portail"><li><span class="bandeau-portail-element"><span class="bandeau-portail-icone"><span class="noviewer" typeof="mw:File"><a href="/wiki/Portail:Chimie" title="Portail de la chimie"><img alt="icône décorative" src="//upload.wikimedia.org/wikipedia/commons/thumb/5/59/Nuvola_apps_edu_science.svg/24px-Nuvola_apps_edu_science.svg.png" decoding="async" width="24" height="24" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/59/Nuvola_apps_edu_science.svg/36px-Nuvola_apps_edu_science.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/59/Nuvola_apps_edu_science.svg/48px-Nuvola_apps_edu_science.svg.png 2x" data-file-width="128" data-file-height="128" /></a></span></span> <span class="bandeau-portail-texte"><a href="/wiki/Portail:Chimie" title="Portail:Chimie">Portail de la chimie</a></span> </span></li> </ul>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; 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