Degree Type
Thesis
Date of Award
1-1-2006
Degree Name
Master of Science
Major
Chemical Engineering
Abstract
A substance that crystallizes into different, but chemically identical, crystalline forms exhibits polymorphism. Polymorphism is generally undesirable in the pharmaceutical industry because properties such as dissolution rate (which, in turn, influences bioavailability), stability, and mechanical compression are intimately linked to crystalline structure. Each polymorph is expected to have a different thermodynamic stability in a particular solvent. One method to determine the thermodynamic stability is by observing the solid-liquid interfacial energy of the polymorphs. In this thesis, the polymorphs of paracetamol (p-Hydroxyacetanilide) crystals in water are studied with molecular dynamics simulation as a first step toward understanding the molecular-level origins of polymorphism. Monoclinic (form I) and orthorhombic (form II) are the known polymorphs of paracetamol. The potential energies of the crystal-water interface for these polymorphs are calculated and the interfacial energies of the (1̄00), (100), (01̄0), (010), (001̄), and (001) faces of each crystal structure are examined to study the relative interaction between the crystal and water at different crystal faces.
Copyright Owner
Yin Yani
Copyright Date
2006
Language
en
OCLC Number
78905144
File Format
application/pdf
File Size
50 pages
Recommended Citation
Yani, Yin, "Solid-liquid interfacial energy of the polymorphs of paracetamol" (2006). Retrospective Theses and Dissertations. 19064.
https://lib.dr.iastate.edu/rtd/19064