Browsing Theses by Supervisor "Roy, PierreNicholas"
Now showing items 110 of 10

Algorithms for quantum molecular dynamics: from matrix product states to path integrals
(University of Waterloo, 20210113)This thesis describes several novel approaches in quantum molecular dynamics for obtaining properties of molecular systems in different regimes. We investigate ground state properties of chains of linear rotors with ... 
Confined Quantum Molecular Degrees of Freedom
(University of Waterloo, 20170922)Motivated by recent experimental measurements of the degeneracy lifting of the rotational ground state of molecular orthoH2 con ned inside the fullerene cage C60 and, more generally, motivated by the physics of con ned ... 
Developments in the Centroid Phase Space Formulation of Quantum Statistical Mechanics
(University of Waterloo, 20160125)The centroid formalism provides a phase space representation of quantum statistical mechanics based on the Feynman path integral. Real time quantum correlation functions can be exactly calculated using the centroid formalism, ... 
Equilibrium and dynamical computation schemes for vibronic models of nonadiabatic systems
(University of Waterloo, 20230106)Two computational schemes were investigated for studying vibronic models of nonadiabatic systems: Path Integral Monte Carlo (PIMC) and vibrational electronic coupled cluster (VECC). A PIMC method was used to investigate ... 
Hybrid Path Integral Monte Carlo/Molecular Dynamics Approach for the Simulation of Rigid Rotating and Translating Molecules
(University of Waterloo, 20200123)The path integral formulation of quantum statistical mechanics [1] is widely used for formulating the partition function and diverse thermodynamic properties. The basic objective of this thesis is to present the benchmark ... 
Path integral ground state approaches for the study of weakly bound clusters and confined molecules
(University of Waterloo, 20180921)This thesis presents the study of weakly bound clusters in the ground state (or the zerotemperature limit) using path integral molecular dynamics. Specifically, we look individually at the quantum properties of small ... 
A path integral Monte Carlo method for obtaining thermodynamic properties of nonadiabatic systems
(University of Waterloo, 20170922)The calculation of thermochemical properties is an important goal of quantum chemistry. Calculation techniques are well established for stable molecules. They are used routinely to calculate Gibbs energy (G) for stable ... 
Quantum Dynamics and Statistical Mechanics of Endohedral Water
(University of Waterloo, 20160907)Since first being synthesized in 2011,H2O@C60 has attracted much attention in the literature. Many interesting quantum phenomena are associated with this system, including orthopara conversion, rotational ground state ... 
Quantum mechanical free energy calculations using path integral molecular dynamics
(University of Waterloo, 20191219)Free energy calculations are one of the most powerful tools within modern theoretical chemistry and are often used to make comparisons with experimental results. Existing free energy calculations are typically performed ... 
Quantum Methodologies for the simulation of molecular hydrogen: from dimers to linear chains
(University of Waterloo, 20201203)Hydrogen has long been considered an ideal model system for a variety of molecular configurations, given its chemical simplicity and ubiquitous nature in the world. However, the weak van der Waals forces that exist between ...