Molecular Structure of Self-Assembled Chiral Nanoribbons and Nanotubules Revealed in the Hydrated State.
A detailed molecular organization of racemic 16-2-16 tartrate self-assembled multi-bilayer ribbons in the hydrated state is proposed where 16-2-16 amphiphiles, tartrate ions, and water molecules are all accurately positioned by comparing experimental X-ray powder diffraction and diffraction patterns...
| Publicado en: | Journal of the American Chemical Society Vol. 130; no. 44; pp. 14705 - 14713 |
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| Autores principales: | , , , |
| Formato: | Artículo |
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American Chemical Society
11/5/2008
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| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=35419292&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 35419292 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 11/5/2008 vid: 130 iid: 44 pid: 997 pub: American Chemical Society artinfo: ui: 35419292 10.1021/ja8048964 ppf: 14705 ppct: 8 formats: tig: atl: Molecular Structure of Self-Assembled Chiral Nanoribbons and Nanotubules Revealed in the Hydrated State. aug: au: Oda, Reiko Artzner, Franck Laguerre, Michel Huc, Ivan affil: Institut Européen de Chimie et Biologie (IECB), Université de Bordeaux-CNRS, UMR 5248, 2 rue Robert Escarpit, F-33607 Pessac Cedex, France Institut de Physique de Rennes, Université Rennes 1, UMR-CNRS 6251, Campus Beaulieu Bat. 11A, 35042 Rennes Cedex, France su: Enantiomers X-ray diffraction Cations Anions Chirality Hydrogen bonding sug: subj: Enantiomers X-ray diffraction Cations Anions Chirality Hydrogen bonding ab: A detailed molecular organization of racemic 16-2-16 tartrate self-assembled multi-bilayer ribbons in the hydrated state is proposed where 16-2-16 amphiphiles, tartrate ions, and water molecules are all accurately positioned by comparing experimental X-ray powder diffraction and diffraction patterns derived from modeling studies. X-ray diffuse scattering studies show that molecular organization is not fundamentally altered when comparing the flat ribbons of the racemate to chirally twisted or helical ribbons of the pure tartrate enantiomer. Essential features of the three-dimensional molecular organizations of these structures include interdigitation of alkyl chains within each bilayer and well-defined networks of ionic and hydrogen bonds between cations, anions, and water molecules between bilayers. The detailed study of diffraction patterns also indicated that the gemini headgroups are oriented parallel to the long edge of the ribbons. The structure thus possesses a high cohesion and good crystallinity, and for the first time, we could relate the packing of the chiral molecules to the expression of the chirality at a mesoscopic scale. The organization of the ribbons at the molecular level sheds light on a number of their macroscopic features. Among these are the reason why enantiomerically pure 16-2-16 tartrate forms ribbons that consist of exactly two bilayers, and a plausible mechanism by which a chirally twisted or helical shape may emerge from the packing of chiral tartrate ions. Importantly, the distinction between commonly observed helical and twisted morphologies could be related to a subtle symmetry breaking. These results demonstrate that accurately solving the molecular structure of self-assembled soft materials—a process rarely achieved—is within reach, that it is a valid approach to correlate molecular parameters to macrocopic properties, and thus that it offers opportunities to modulate properties through molecular design. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2008 holdings: @attributes: islocal: N |
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