Herringbone type structure

In contrast, the unsubstituted oligomer para-hexaphenyl is a highly crystalline material.6 In the crystalline state, the oligomer chains are arranged in layers forming a herringbone-type structure as shown in Fig. 8.2, characterized by a unit cell a = 8.091 °A,b = 5.568 X,c = 26.241 X, and ft = 98.17°. Two types of preferred crystalline growths are observed.7 One of them is oriented with the (00/) and the other with the (22-3) plane parallel to the surface of the substrate. 

Some limited mobility of the alkanes was detected by solid state DNMR as a function of temperature [117], This mobility explains why alkanes such as pentane can be driven out of the ICs by heating, leaving behind empty channel structures that differ from the well known native herringbone type structures of CDs [118],... 

Recently, by crystal structure studies the number of different polymorphs of Copper Phthalocyanine Blue has been extended to nine, various of which are differing mainly in herringbone-type interaction [17]. 

Historically, wrinkles on PDMS were first observed upon metal evaporation. Martin and coworkers reported wrinkle formation by evaporation of aluminum onto PDMS [39], which was first not followed further. The potential of metal evaporation onto PDMS for structuring purposes was recognized only 17 years later by Bowden [15]. In these experiments, the metal was coated onto thermally expanded PDMS. Returning the sample to room temperature causes thermal shrinkage of the PDMS and consequently wrinkling of the top layer. Chen and coworkers have theoretically shown that the herringbone-type pattern observed under these conditions... 

Fig. 1 a-c Schematic representation of a channel type b cage herringbone type c cage brick type, crystal structures formed by crystalline cyclodextrin inclusion complexes. (Adopted from [18] with permission)... 

Figure 3.3 TEM images of the two common VACNF internal structures (a) herringbone-type nanofiber grown from Ni catalyst and (b) bamboo-type nanofiber grown from Fe catalyst at the same conditions. Reprinted with permission from [4].

The structural an yses indicate a substantial change of the unit cell lattice symmetry during this transition. This is expected since based on the definition of the Su phase, the laterd packing perpendicular to the chain direction is no longer hexagonal, but is orthorhombic with a herringbone type (7,2). It can be seen from the WAXD... 

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