Computational Aspects of Polymorphism

• Published in: Polymorphism in Molecular Crystals p. 1
• Main Author: Bernstein, Joel
• Format: Book Chapter
• Language: English
• Published: Oxford Oxford University Press 2020; Oxford University Press, Incorporated
• Edition: 2nd Edition
• Subjects: General Engineering & Project Administration; General References; molecular energetics; conformational polymorphism; comparison of polymorphic structures; crystal structure prediction; crystal energetics
• ISBN: 0199655448; 9780199655441
• DOI: 10.1093/oso/9780199655441.003.0005

The application of computational techniques to polymorphic systems is reviewed. Topics covered include the energetics of molecular geometric features (bond lengths, bond angles, torsion angles) and the energetics of intermolecular interactions of various types. Methods and techniques for the presentation of polymorphic structures are described, followed by some historically important early examples of conformational polymorphism. The latter subject is treated in light of recent developments, including some exemplary studies of conformational polymorphism and the prototypical example of “ROY” is discussed in detail. The computational prediction and comparison of polymorphs is discussed in the framework of the computational prediction of crystal structures. Methods discussed on polymorphs include the comparison based on geometric criteria, comparison based on Hirshfeld surfaces, a comparison based on energetic environment, comparison of X-ray diffraction patterns, and the use of partitioned lattice energy to investigate the details of similarities and differences in polymorphic structures.