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\usepackage{enumitem} | 
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\begin{document} | 
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\frontmatter | 
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\title{APPLICATION AND DEVELOPMENT OF MOLECULAR DYNAMICS TECHNIQUES FOR THE  | 
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STUDY OF WATER}      | 
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\title{DEVELOPMENT OF MOLECULAR DYNAMICS TECHNIQUES FOR THE  | 
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STUDY OF WATER AND BIOCHEMICAL SYSTEMS}      | 
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\author{Christopher Joseph Fennell}  | 
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\work{Dissertation} | 
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\degprior{B.Sc.} | 
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\maketitle | 
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\begin{abstract} | 
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This dissertation comprises a body of research in the field of | 
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classical molecular simulations, with particular emphasis placed on | 
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the proper depiction of water. It is arranged such that the techniques | 
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and models are first developed and tested before being applied and | 
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compared with experimental results. Accordingly, the first chapter | 
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starts by introducing the technique of molecular dynamics and | 
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discussing technical considerations needed to correctly perform | 
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molecular simulations. | 
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The second chapter builds on these consideration aspects by discussing | 
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correction techniques for handling long-ranged electrostatic | 
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interactions. Particular focus is placed on the damped shifted force | 
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({\sc sf}) technique, and it is shown to be nearly equivalent to the | 
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Ewald summation in simulations of condensed phases. Since the {\sc sf} | 
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technique is pairwise, it scales as $\mathcal{O}(N)$ and lacks | 
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periodicity artifacts. This technique is extended to include | 
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point-multipoles, and optimal damping parameters are determined to | 
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ensure proper depiction of the dielectric behavior of molecular | 
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systems. | 
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The third chapter applies the above techniques and focuses on water | 
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model development, specifically the single-point soft sticky dipole | 
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(SSD) model. In order to better depict water with SSD in computer | 
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simulations, it needed to be reparametrized, resulting in SSD/RF and | 
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SSD/E, new variants optimized for simulations with and without a | 
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reaction field correction. These new single-point models are more | 
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efficient than the more common multi-point models and better capture | 
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the dynamic properties of water. SSD/RF can be used with damped {\sc | 
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sf} through the multipolar extension described in the previous | 
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chapter. | 
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The final chapter deals with a unique polymorph of ice that was | 
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discovered while performing simulations with the SSD models.  This | 
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form of ice, called ``imaginary ice'' (Ice-$i$), has a low-density | 
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structure which is different from any previously known ice | 
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polymorph. The free energy analysis discussed here shows that it is | 
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the thermodynamically preferred form of ice for both the single-point | 
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and commonly used multi-point water models.  Including electrostatic | 
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corrections is necessary to obtain more realistic results; however, | 
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the free energies of the studied polymorphs are typically so similar | 
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that system properties, like the volume in $NVT$ simulations, can | 
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directly influence the ice polymorph expressed. | 
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\end{abstract} | 
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\begin{dedication} | 
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I would to thank my advisor, J. Daniel Gezelter, for the guidance, | 
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perspective, and direction he provided during this work. He is a great | 
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teacher and helped fuel my desire to learn. I would also like to thank | 
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my fellow group members - Dr.~Matthew A.~Meineke, Dr.~Teng Lin, | 
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Charles F.~Vardeman~II, Kyle Daily, Xiuquan Sun, Yang Zheng, Kyle | 
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S.~Haygarth, Patrick Conforti, Megan Sprague, and Dan Combest for | 
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helpful comments and suggestions along the way. I would also like to | 
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thank Christopher Harrison and Dr. Steven Corcelli for additional | 
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discussions and comments. Finally, I would like to thank my parents, | 
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Edward P.~Fennell and Rosalie M.~Fennell, for providing the | 
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opprotunities and encouragement that allowed me to pursue my | 
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interests, and I would like to thank my wife, Kelley, for her | 
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unwaivering support. | 
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my fellow group members - Dr.~Matthew Meineke, Dr.~Teng Lin, Charles | 
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Vardeman~II, Kyle Daily, Xiuquan Sun, Yang Zheng, Kyle Haygarth, | 
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Patrick Conforti, Megan Sprague, and Dan Combest for helpful comments | 
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and suggestions along the way. I would also like to thank Christopher | 
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Harrison and Dr.~Steven Corcelli for additional discussions and | 
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comments. Finally, I would like to thank my parents, Edward and | 
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Rosalie Fennell, for providing the opportunities and encouragement | 
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that allowed me to pursue my interests, and I would like to thank my | 
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wife, Kelley, for her unwavering support. | 
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\end{acknowledge} | 
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\mainmatter |