| dc.contributor.author | Hernandez de la Pena, Lisandro. | en_US |
| dc.date.accessioned | 2014-10-21T12:37:07Z | |
| dc.date.available | 2004 | |
| dc.date.issued | 2004 | en_US |
| dc.identifier.other | AAINR00946 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10222/54674 | |
| dc.description | Water's unusual properties have continuously fascinated researchers from different areas. Yet, in spite of the vast amount of information collected to date, the fitting together of all the different pieces into a coherent picture has proven to be extremely difficult. A detailed account of isotopic effects, as a specific example of these problems, requires the inclusion of the quantum nature of the protons. | en_US |
| dc.description | Methods based on Feynman's path integral representation of statistical mechanics have been extensively used to calculate equilibrium properties of quantum systems in condensed phase. They allow standard classical methods, such as molecular dynamics, to be used for the simulation of an otherwise quantum system at finite temperature. Furthermore, approximate quantum dynamical information has also become available through the use of the centroid molecular dynamics (CMD) methodology. | en_US |
| dc.description | In this thesis, a CMD methodology for systems of rigid bodies is developed by introducing the concept of an orientational centroid and by designing an algorithm that samples homogeneously the quantum mechanical orientational uncertainty while ensuring centroid conservation. This rigid body-CMD technique, which is significantly more efficient than the standard CMD method, is extensively applied to the study of quantum effects in liquid water and ice Ih. | en_US |
| dc.description | Quantum effects on the equilibrium and dynamical properties of liquid H2O and D2O are studied and are shown to agree with previous results. The present method dramatically improves the agreement with experimental isotopic differences relative to those obtained with classical simulations. Quantization is found to significantly affect the properties of liquid water over a wide range of temperatures, especially in the low temperature region. An unusual behaviour of the quantum mechanical molecular uncertainty is identified and its relationship to the local environment is determined. The "effective tunneling" in liquid water is directly characterized as part of a detailed analysis of the interrelationship between structure and dynamics. Quantum effects in ice Ih are also investigated in detail and are found to be significant. | en_US |
| dc.description | Thesis (Ph.D.)--Dalhousie University (Canada), 2004. | en_US |
| dc.language | eng | en_US |
| dc.publisher | Dalhousie University | en_US |
| dc.publisher | | en_US |
| dc.subject | Chemistry, Physical. | en_US |
| dc.title | Quantum molecular dynamics of liquid water and ice. | en_US |
| dc.type | text | en_US |
| dc.contributor.degree | Ph.D. | en_US |
