Channel-type structure

C36H60O30,C6H5O3S -Na+-10 H20 Cyclomaltohexaose - sodium ben-zenesulfonate, decahydrate (CDXBZS)275 P212121 Z = 2 D = 1.47 R = 0.07 for 2,894 intensities. This is a channel-type structure, with a conformation very similar to that of the potassium acetate280 and Methyl Orange complexes.281 All of the pyranose residues have the 4Cl conformation, and the primary alcohol groups are in the gauche-trans orientation. 

Channel-type structures are formed in the case of trans-s til bene and benzene as guests. In these cases at least two independent channels are... 

Figure 8. A stereoscopic view of the packing in the inclusion compound of 1,1,6,6-tetraphenylhexa-2,4-dyne-1,6-diol, 2, with (a) chalcone and (b) 9-anthraldehyde. 9-Anthraldehyde gives cage-type and chalcone gives channel-type structures. [Reproduced with permission from F. Toda, Topics Curr. Chem. 140, 43 (1987).]...

Moreover Channel type structure is effective for transversely spreading of the coupled fundamental wave. This type of structure can be applied sufficiently to semiconductor laser operation in SHG. And this idea can be applied to other materials. 

Figure 5. (b) The channel-type structure of inclusion compounds of urea viewed along the c axis. For clarity the guest molecules are represented by large circles. (Data from ref. 36a). 

P2i2i2i Z = 2 D, = 1.48 R = 0.10 for 2,246 intensities. This structure is nearly isomorphous with that of the sodium benzenesulfonate complex. It is a channel-type structure, with the cyclomaltohexaose molecules stacked head-to-tail. The two m-nitrophenol molecules are disor-... 

Harada et al. [44] have found that 6-aminocinnamoyl fi-CD (6-aminoCiO- -CD) is sparingly soluble in water, although most 6-modified CDs are soluble. Figure 3.10 shows the structures of 6-aminoCiO-y -CD in the crystal. 6-AminoCiO-]S-CD was found to form a dimer tightly stacked by intermolecular hydrogen bonding to form a head-to-head channel-type structure. 

The cage-type packing structure is frequently observed for relatively small guest molecules which can be enclosed in the host cavity. CyD molecules are arranged in a herring-bone fashion and both ends of the host cavity are closed by adjacent molecules to create an isolated "cage (Fig. 7.13A). The channel-type structure is... 

The channel-type structure is formed with a variety of guest molecules. Generally, anionic guests, such as, acetate [91], 1-propanesulfonate [92], benzenesulfo-nate [93], y-aminobutyrate [94], and Methyl Orange [95] 14 are preferentially included in positively charged cylindrical channels. In contrast, metal cations are... 

The dimeric structure of j8-CyD is most frequently observed as a building block of crystal structures. There are two types of arrangement of the dimer unit. In the head-to-head channel-type structure, the dimer unit is arranged to form an infinite linear channel. The other type is the layer-type structure, in which dimer units are arranged to form a chess-board-like pattern. Both ends of the dimer cavity are open to the intermolecular space in the adjacent layer. 

In the channel-type structure, the dimer units are linearly stacked or helically arranged on the crystallographic two-fold axis. In the former structure, the dimer unit coincides with the repetition unit. A variety of guest molecules, such as ethanol [135], m-iodobenzoic acid [136], benzocaine [137] 25, iodine-iodide [138], 3,3-dimethylbutylamine [139], pyrene [140], trans-cinnamic acid [141], 4,7-dimethyl-... 

Fig. 7.18. A head-to-tail channel-type structure observed in the f-CyD complex A/ith meclofenamate (A) and a head-to-head channel-type structure in the p-hydroxybenzaldehyde complex (B).

Fig. 7.19. Head-to-head channel-type structures observed in the y-CyD complex A/ith potassium (12-cro A/n-4)2 (A) and the <5-CyD complex A/ith cycloundecanone (B).

Current P3AT structure studies encompass a myriad of specialized syntheses and settings that relate to specific applications. One interesting variant, clearly with a more fundamental relevance, is a class of inclusion compounds in which molecular structural self-assembly yields channel-type structures that can be occupied by linear arrays of individual polymers or oligomers [278,279]. In this way, the interchain distances and couplings can be systematically defined and then studied. 

Channel-type structure of (CH3 )4 N BO(OH)f 2 (NH2 )2 CO H2 0(12). In compound 12 [5c], both independent urea molecules and the BO(OH)2 ion in the asymmetric unit occupy special positions of symmetry m such that only the C-O or B-O bond lies on the mirror plane. A projection of the crystal structure along the [010] direction is presented in Figure 8.22. The host lattice consists of a parallel arrangement of unidirectional channels whose cross-section has the shape of a peanut. The diameter of each spheroidal half is about 7.04 A, and the separation between two opposite walls at the waist of the channel is about 5.85 A. The well-ordered tetramethylammonium cations are accommodated in double columns within each channel. 

Channel-type structure of [(C2H5)4N ]2C4 0l 4(NH2)2CS-2H2 0 (16). The host lattice of 16 [6a] contains large 1-D rectangular channels extending parallel to the a-axial direction, as illustrated in Figure 8.32. 

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