Inorganic Chemistry III, University of Bayreuth, Universitätsstrasse 30, 95447, Bayreuth, Germany.
Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK.
Angew Chem Int Ed Engl. 2017 Apr 10;56(16):4432-4437. doi: 10.1002/anie.201612122. Epub 2017 Mar 20.
Columnar supramolecular phases with polarization along the columnar axis have potential for the development of ultrahigh-density memories as every single column might function as a memory element. By investigating structure and disorder for four columnar benzene-1,3,5-trisamides by total X-ray scattering and DFT calculations, we demonstrate that the column orientation, and thus the columnar dipole moment, is receptive to geometric frustration if the columns aggregate in a hexagonal rod packing. The frustration suppresses conventional antiferroelectric order and heightens the sensitivity towards collective intercolumnar packing effects. The latter finding allows for the building up of mesoscale domains with spontaneous polarization. Our results suggest how the complex interplay between steric and electrostatic interactions is influenced by a straightforward chemical design of the molecular synthons to create spontaneous polarization and to adjust mesoscale domain size.
具有沿柱状轴偏振的柱状超分子相具有发展超高密度存储器的潜力,因为每个柱状相都可以作为一个存储元件。通过对四个柱状苯-1,3,5-三酰胺的结构和无序性进行全 X 射线散射和 DFT 计算,我们证明如果柱状相在六方棒状堆积中聚集,那么柱状相的取向,从而柱状偶极矩,容易受到几何阻挫的影响。这种阻挫抑制了常规反铁电有序,并提高了对集体柱状间堆积效应的敏感性。后一种发现允许构建具有自发极化的介观畴。我们的结果表明,通过对分子单体进行简单的化学设计来创建自发极化和调整介观畴尺寸,如何影响空间和静电相互作用之间的复杂相互作用。