Coordination networks from aromatic thioether building blocks for potential sensing and semiconductive applications

Abstract

The incorporation of ever more sophisticated organic functionality is a topical issue of both fundamental and practical importance in the fast-growing field of coordination networks, as one major advantage of these networks hinges upon the much richer chemical functionalities in comparison to the inorganic crystalline materials. In this connection, we present particular interests in the large and complex organic molecules based on thioethers as the building blocks which can offer richer functional diversity that provides for advanced materials properties in the prospective solids. In comparison with the cases in other common ligands such as nitriles and pyridyls, the exceptional bonding behavior of thioethers is helpful for constructing crystalline coordination networks with large-size and complex structures. For this, three versatile molecules: one with three 1,2,3-tris(methylthio)phenyl groups, one porphyrin molecule with four 1,2,3-tris(phenylthio)phenyl groups and one starburst molecule with six 4-methylthiophenyl groups attached to the triphenylene core are crystallized with different Ag(I) ions to form a number of new structures. And a group of large aromatic selenoether ligands such as 1,3,6,8-tetrakis(phenylseleno)pyrene and 2,3,6,7,10,11-hexakis(phenylseleno)triphenylene are used to crystallize with silver salts to form (10, 3)-a nets with the non-centrosymmetric and non-interpenetrating features. Furthermore, one diamondoid network with remarkable and sensitive size-selectivity for small aromatic guests is made from the large tetrapod tetrakis[(4-methylthiophenyl)ethynyl]silane and AgBF4 salt. We also aim to explore the regular structural patterns and the associated electronic properties of a group of hybrid networks based on BiBr3 and aromatic thioethers, with emphasis on structurally correlating the organic molecules with the BiBr3 aggregates as well as the overall hybrid networks. By using multidentate ligands with open geometries, we achieves hybrid BiBr3-aromatic thioether networks with open framework and higher dimensional (e.g., 3D) features that are potentially amenable to further study on guest exchange experiments. Diffuse reflectance measurements on the hybrids and the organic molecules reveal significant electronic interactions between the inorganic and organic components, which make these hybrids have the potential semiconductive applications in the solid state chemistry.

Date of Award	16 Feb 2009
Original language	English
Awarding Institution	City University of Hong Kong
Supervisor	Zhengtao XU (Supervisor) & Lee Ping Lilian VRIJMOED KWAN (Supervisor)