Layered hybrid solids

Layered Perrhenate and Vanadate Hybrid Solids On the Utility of Structural Relationships... 

The flexibility of polyoxovanadate species [VxOy]" to adopt a wide variety of structural configurations, such as rings, chains, and layers, is reflected in their predominance in a wide variety of hybrid solids. For example, approximately sixteen distinct hybrid vanadium oxides based solely on V205 layers, with about nine different layer types, have currently been synthesized [34—47]. Layered structures of... 

The rate of energy and electron transfer in any of these systems is an ensemble average of all sites within the layered assembly, and thus there is no single rate for any of the processes in the assemblies. Nonetheless, in addition to the increased quantum yield, assemblies constructed with the HTiNbOs spacer exhibit a long-lived charge-separated state component not observed in the a-ZrP spaced assemblies, of x = 900 ps. While there is still much to be learned from the study of multi-chromophore arrays, this synthetic approach appears to hold much promise for the creation of organic-inorganic hybrid solid state devices. 

A classification of methods for preparing polymer-layered inorganic solid compounds takes into account the main processes involved in the synthesis of the final hybrid material. The nature of both the 2D host solid and the guest polyma- determines the pathway applicable to obtain a particular nanocomposite and, in certain cases, is decisive in the behavior of the resulting material. In... 

This highhght examines several new hybrid layered structures in the hetero-metallic perrhenate and vanadate families, whereby the late transition-metals are incorporated and their roles probed in the structures of layered solids. From these two families, new structural principles have emerged that not only help us understand key stractural features and correcdy forecast new compositions, but equally, have yielded many surprises (chirality, reduced phases) that show some of the most exciting chemistry is still waiting to be discovered or even imagined ... 

Successive H-bond urea self-assembly of 4 and sol-gel transcription steps yield preferential conduction pathways within the hybrid membrane materials. Crystallographic, microscopic and transport data confirm the formation of self-organized molecular channels transcribed in solid dense thin-layer membranes. The ionic transport across the organized domains illustrates the power of the supramolecular approach for the design of continual hydrophilic transport devices in hybrid membrane materials by self-organization (Figure 10.8) [42-44]. 

---