ISSN:
0022-3832
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Various problems related to the determination with x-rays of the atomic configuration of organic fibers are discussed. Because of the approximate nature of the underlying theory, too far-reaching conclusions should be avoided, especially since, in the case of organic fibers, the situation is much less simple than in the case of sodium chloride powder or metallic wires, for example. Because of these facts, and because of the relative poorness of fiber patterns, the atomic coordinates as well as the space group of the structure can be found only within certain limits. Though the use of macroscopic models is very helpful in visualizing the spatial arrangement, no conclusions of a quantitative nature can be reached with their aid because the assumptions embodied in these models are too numerous and too inexact to justify speculations on details of the structure. In the case of cellulose fibers, it is shown that the problem cannot yet be solved completely; the outlook for a really unique solution is not hopeful. The structure proposed by Meyer and Misch is still the best approximation available. More recent propositions are shown to be less well founded; the atomic configuration introduced by Peirce, being at variance with chemical, crystallographic and x-ray evidence, is to be discarded.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1947.120020603
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