Short-Range Order in Glycerol. A Molecular Dynamics Study.
01 January 1989
A molecular model has been constructed for glycerol and has been applied to a study of clusters and condensed phases by molecular dynamics simulation. Each molecule is regarded as a flexible polar complex of nine mass points (CH and CH sub 2 groups are treated as ``united atoms''). Periodic arrays stabilize in a close approximation to the observed glycerol crystal structure, with identical extended molecules connected by infinite chains of hydrogen bonds. By contrast the stable and supercooled liquids display a variety of asymmetrical molecular conformations and an irregular network of hydrogen bonds. Detailed examination of the various atomic pair correlation functions reveals considerable overlap of intramolecular and intermolecular features, implying intrinsic ambiguity in the interpretation of X-ray and neutron diffraction measurements designed to determine the short-range order of liquid glycerol.