End gauche

An FTIR comparison between C18 and C30 sorbents prepared by both surface-and solution-polymerized synthetic routes over a range of temperatures was recently described [119]. Little difference in conformational order was observed for C30 sorbents prepared by both surface and solution-polymerized synthetic routes, as indicated by kink/gfg, double- and end-gauche conformations. Differences in conformational... 

The notation of Maroncelli et al. (20,21) will be followed in discussing conformation, so that, in our designation of the conformational state of a CD2 group, the CC bonds that are directly bonded to the CD2 group will be underlined. Thus t means the CD2 moiety connects a trans and a gauche bond. End-gauche conformations... 

The time-resolved spectra from the run of C16 exposed to C12E04 (Figure 3) are quite different from those of the surfactant - free water run. The relative intensity of the end gauche and double gauche defect bands is increased, and the kink defect band bear 1300 cm 1 may be split into a multiplet. In addition, several bands between 1260 and 1200 cm 1 are enhanced, relative to the spectrum of the... 

The process of melting can be described in the following way the rraru-planar structure of the tram chains collapses (observations (i), (j) and (t)) and conformational disorder takes place aceompanied by the appearance of the following conformational defects GG, GTG, GTG (observations (j) and (1)), end-gauche (observation (u)) and gauche in general (observations (b), (t), (y), (v), (w), and (x)). In practice we find characteristic signals of liquid-like structures. 

For translational motions, the mean value of the translational diffusion coefficient is 6.10 cm s at 300 K and it is of the same order of magnitude as those already proposed for n-tricosane or n-tritriacontane. Finally, it is noteworthy that the diffusion length (L = 2.7-2.8 A) corresponds roughly to two -CH2- units, a result which supports the formation of end gauche defects within the interlamellar space, the chains remaining in an almost extended form in their central part. 

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