Reticular net

Figure 2.1 Fear responses involve the activation of many brain areas. The hypothalamus controls physical changes in the body, such as increased blood pressure and dilated pupils. The central gray area causes freezing behavior, the reticular net triggers a reflex response, and norepinephrine increases attention.

Netz-, wetting, steeping net, netting, reticular, omental. -adern,/.pi. netted veins or cracks. 

In ionic solids, the reticular positions are occupied by ions (or anionic groups) of opposite charge. In NaCl, for instance (figure I.2A), the CR ions are surrounded by six Na ions. The alternation of net charges gives rise to strong coulombic interactions (see section 1.11.1). 

Reticular, (adjective) having the form of a (usually periodic) net. 

The term reticular refers to anything with a net or network property in Somalia and neighboring countries, for example, one can, with a bit of luck, find the reticulated giraffe[2]. The term reticular chemistry has been coined to describe the chemistry of making network compounds. " So far, this term has been used only sparingly in scientific literature. However, we find the related word isoreticular very useful, as there is no other term describing two compounds that form nets with the same topology but with different chemical constituents. 

The ideal net topologies are not only useful when understanding and comparing strucmres, they can also serve as blueprints in the design of new network compounds. Thus, while the most symmetric nets, as the dia net, were an inspiration for the early work by Robson and his group, the catalogs of different nets that can be found on-line in the RCSR (Reticular Chemistry Structural Resomce database) and in other sources" can serve as an inspiration to twenty-first-century synthetic chemists. 

RCSR Reticular Chemistry Structural Resource, a database containing the topology symbols and other information for 2D and 3D nets. 

It has also been argued that the practice of crystal engineering has been around much longer than the term itself [51]. Nevertheless, crystal engineering is today a wide field where the deliberate construction of 3D-nets is a subfield. To classify this a new term has been put forward, i.e. reticular chemistry [4,5,30,54]. The definition reads ...the practice of logical synthesis... 

Table 10.4 The nets that are known to have dual nets that are identical to the original nets, (selfdual). Extracted from the Reticular Chemistt> Structural Resource database fl31-...

Assign the correct net to the structure by comparing the net to schematic views in this or other books [5-7] or using the Reticular Chemistry Structure Resource [8]. If you are unsure of the net, count rings. An example on how to count rings can be found in Chapter 4. 

Once the richness of the field was discovered, it was necessary to rationalize the synthesis of MOFs to provide tailor-made architectures. At the beginning, the reticular chemistry of the augmented net concept of O Keeffe et al. [56] was nicely applied for defining the chemical and topological rules governing this possible design. The derived structures of MOF-5 [4] provide the most famous example of this approach. 

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