ISSN:
1600-5767
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Geosciences
,
Physics
Notes:
Diesel waxes containing n-alkanes in the range n\,=\,9–30 show only two types of X-ray diffraction pattern. When indexed these are seen to belong to the orthorhombic space groups Bb21m and Fmmm; they are isostructural with two binary phases, one phase having n\,=\,24 and 26 and the other n\,=\,22 and 24. We designate these the low-disorder (LD) and high-disorder (HD) phases, respectively. From the long spacings shown in the XRD patterns, it is possible to calculate the percentage of void space present in the wax crystals. It is found that the larger the spread of n values in the wax composition (i.e. the larger the variance in chain length), the greater the tendency to crystallize in the HD form and the more extensive the voids.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0021889898012801
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