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On the irrelevance of electrostatics for the crystal structures and polymorphism of long even n-alkanes

✍ Scribed by Jacco Van de Streek; Paul Verwer; Piet Bennema; Elias Vlieg

Publisher
John Wiley and Sons
Year
2002
Tongue
English
Weight
122 KB
Volume
23
Category
Article
ISSN
0192-8651

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✦ Synopsis

Abstract

It is known that the experimental triclinic crystal structures of even n‐alkanes are not well reproduced upon energy minimization with current force fields. The inclusion of electrostatics does not solve this, and, moreover, some charge schemes show unphysical features such as positively charged carbon atoms or charge alternation. The effect of the electrostatics on the energies of the crystal structures of the even n‐alkanes, and thereby on their polymorphism, has never been established. A new charge scheme is introduced that yields physically sensible charges without constraints. It will also be shown, however, that electrostatics are relevant neither for the structures of the crystals, nor for their energies. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 365–370, 2002

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