Supramolecular columnar structures

In all of these cases, the products of the reactions did not exhibit any luminescence when irradiated with U V light. This result was not surprising since the rupture of the columnar structures of the starting materials with the interleaved fluorenones probably led to a loss of luminescence. In fact, luminescence in these systems seems to he associated with the supramolecular organization of the solid. 

In the case of the trinuclear [ t-N1,C2-bzimAu]3 (bzim = benzylimidazolate), in addition to the extended structures that form with other metals (see Section 6.3), it also forms supramolecular networks, acting as an electron donor with small organic acids [48]. For example, it reacts with TCNQ (tetracyanoquinodimethane) giving rise to a columnar structure in which each TCNQ molecule is sandwiched between two units of the trinuclear complex in a face-to-face manner. Thus, the repetition of this pattern leads to a stacking of the type (Au3)(Au3)( t-TCNQ)(Au3)... 

The introduction of such ligands into the Ag2C2-containing system has led to isolation of supramolecular complexes showing chain-like or columnar structures. 

Disklike tetramer 38 of folic acid derivative containing oligo(glutamic acid) moieties has both thermotropic columnar and micellar cubic (Pm3n) phases [53-56]. By the addition of sodium salt, 38 forms supramolecular chiral structures in the columnar and cubic phases (Fig. 5.7). The formation of supramolecular chiral stmctures in the colunmar phase is due to the interactions between the hydrogen bonded disks and the ions [57, 58]. 

Stenzel. V. Jeske, J. du Mont. W. Jones. P.G. Supramolecular soft-soft interactions of diiodo( err-butyl)-(isopropyljphosphonium cations with p2 to p5—Bridging iodide anions. Formation of chains, helixes and columnar structures. Inorg. Chem. 1997. 36. 443. 

As mentioned above, the HBC derivatives substituted with alkyl chains can form self-assembled ID columnar structures due to strong n-n interactions between the rigid aromatic core and the nanoscale phase separation between the rigid core and the flexible alkyl chains at the periphery, which facilitates the overlap of n-orbitals between neighboring planes and maximizes the charge transport abUity along the ID columns. Therefore the control of supramolecular order of HBC derivatives... 

Ionic interactions can be used for the preparation of supramolecular side-chain polymers [109-111], The interactions between -SO and -NH and those between -COO and -NH give liquid-crystalline polymeric complexes. The complex of poly(ethylene oxide)-fc ocfc-poly(L-lysine) and a carboxyl-functionalized hexa-peri-haxabenzocornene (30) shows columnar structures (Figure 23) [109], Polymeric complex 31 forms a stable smectic phase [111], This complex shows... 

In addition to exhibiting bioactivities, polyfluoroaromatic compounds often display unique properties for accessing supramolecular architectures in crystalhne states. Arene and polyfluoroarene molecules are well known to alternately stack through interactions in their 1 1 co-crystals to give columnar structures [116]. 

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