Volume 5 Issue 6, June 2013

Volume 5 Issue 6

The self-assembly of materials is driven by many competing processes. Christopher Murray, Sharon Glotzer and colleagues have now experimentally and computationally studied the self-organization of thin lanthanide fluoride nanoplates at the liquid/air interface. Various twodimensional planar tilings are observed and a simulated example of one such pattern can be seen on the cover. The assembly behaviour can be understood by considering both the directional attractions between the particles, which are caused by patchy ligand coverage, and their shape.

Article p466

IMAGE: MICHAEL ENGEL, JAIME A. MILLAN, SHARON C. GLOTZER (UNIV. MICHIGAN)

COVER DESIGN: ALEX WING

Thesis

  • Thesis |

    Michelle Francl ponders ways in which we can talk about chemistry without triggering chemophobia.

    • Michelle Francl

Books and Arts

Research Highlights

Blogroll

News and Views

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    • Masaki Uchida
    •  & Trevor Douglas
  • News & Views |

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    • Yonggang Wang
    •  & Yongyao Xia
  • News & Views |

    A combined theoretical and experimental approach has revealed that radicals can be significantly stabilized by the presence of a remote anionic site in the same molecule. This finding has implications for understanding and potentially controlling the reactivity of these important reactive intermediates.

    • Malcolm D. E. Forbes
  • News & Views |

    A pH-responsive inorganic membrane has been devised that acts as a gatekeeper for the transport of charged solutes into and out of its interior volume. This behaviour was further used to regulate an enzymatic reaction.

    • Christine D. Keating
  • News & Views |

    A complex featuring a uranium(VI) terminal nitride functional group has been isolated through mild oxidation, and shown to be highly reactive. Under photolysis, it converts into a compound that is capable of C–H bond activation.

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Review

  • Review Article |

    Two-dimensional polymers, which exhibit periodic bonding in two orthogonal directions, offer mechanical, electronic and structural properties distinct from their linear or irregularly crosslinked polymer counterparts. Their potential is largely unexplored because versatile and controlled synthetic strategies are only now emerging. This Review describes recent developments in two-dimensional polymerization methods.

    • John W. Colson
    •  & William R. Dichtel

Articles

  • Article |

    Thin lanthanide fluoride nanoplates are shown to self-organize at the liquid/air interface into long-range-ordered two-dimensional planar tilings. In this joint experimental–computational, multiscale investigation, the assembly behaviour is shown to be dictated by entropic forces arising from particle shape and enthalpic forces arising from interaction anisotropy.

    • Xingchen Ye
    • , Jun Chen
    • , Michael Engel
    • , Jaime A. Millan
    • , Wenbin Li
    • , Liang Qi
    • , Guozhong Xing
    • , Joshua E. Collins
    • , Cherie R. Kagan
    • , Ju Li
    • , Sharon C. Glotzer
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  • Article |

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    • , David L. Marshall
    • , Stephen J. Blanksby
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    • , Stefan A. Freunberger
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    •  & Peter G. Bruce
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    • J. Snijder
    • , C. Uetrecht
    • , R. J. Rose
    • , R. Sanchez-Eugenia
    • , G. A. Marti
    • , J. Agirre
    • , D. M. A. Guérin
    • , G. J. L. Wuite
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    • Jing Li
    • , Justin S. Cisar
    • , Cong-Ying Zhou
    • , Brunilda Vera
    • , Howard Williams
    • , Abimael D. Rodríguez
    • , Benjamin F. Cravatt
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  • Article |

    A polymerization method for converting elemental sulfur into a chemically stable, processable and electrochemically active copolymer has been described. This methodology — termed inverse vulcanization — is conducted by a one-step process using liquid sulfur, as both reaction medium and reactant, and vinylic comonomers to form polymeric materials with a high content of sulfur (50–90 wt%).

    • Woo Jin Chung
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    • , Jeong Jae Wie
    • , Ngoc A. Nguyen
    • , Brett W. Guralnick
    • , Jungjin Park
    • , Árpád Somogyi
    • , Patrick Theato
    • , Michael E. Mackay
    • , Yung-Eun Sung
    • , Kookheon Char
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  • Article |

    Removing Mg2+ from RNA and replacing it with Fe2+ confers on some RNAs the ability to catalyse single-electron transfer. Here, it is hypothesized that Fe2+ was an RNA cofactor on the early Earth, when iron was benign and abundant, and was replaced by Mg2+ during a period known as the great oxidation, brought on by photosynthesis.

    • Chiaolong Hsiao
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In Your Element

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Corrigenda