Synthesis, Characterization and Study of Liquid Crystals Based on the Ionic Association of the Keplerate Anion [Mo132O372(CH3COO)30(H2O)72]42− and Imidazolium Cations

Inorganics

Nancy Watfa⁴  Sstien Floquet⁴  Emmanuel Terazzi¹  William Salomon⁴  Laure Guénພ¹  Kerry Lee Buchwalder¹  Akram Hijazi³  Daoud Naoufal³  Claude Piguet¹  Emmanuel Cadot⁴  Greta Ricarda Patzke² 

[1] Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, Geneva CH-1211, Switzerland; E-Mails:Institut Lavoisier de Versailles, UMR 8180, University of Versailles, 45 avenue des Etats-Unis, Versailles 78035, France;;Laboratoire de Chimie de Coordination Inorganique et Organométallique LCIO, Université Libanaise, Faculté des Sciences I, Hadath, Lebanon; E-Mails:;Institut Lavoisier de Versailles, UMR 8180, University of Versailles, 45 avenue des Etats-Unis, Versailles 78035, France; E-Mails:

关键词: polyoxometalates;    Keplerate;    cluster;    liquid crystal;   

DOI  :  10.3390/inorganics3020246

来源: mdpi

【 摘 要 】

A series of eight new materials based on the ionic association between 1-methyl-3-alkylimidazolium cations and the nanometric anionic Keplerate [Mo₁₃₂O₃₇₂(CH₃COO)₃₀(H₂O)₇₂]⁴²⁻ has been prepared and characterized in the solid state. The liquid crystal properties of these materials were investigated by the combination of Polarized Optical Microscopy, Differential Scanning Calorimetry and Small-angle X-Ray Diffraction showing a self-organization in lamellar (L) mesophases for the major part of them. From the interlamellar spacing h and the intercluster distance a_hex, we demonstrated that the cations are not randomly organized around the anionic cluster and that the alkyl chains of the cations are certainly folded, which limits the van der Waals interactions between the cations within the liquid crystal phase and therefore harms the quality of the mesophases.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.