Abstract

Quantum mechanical calculations have emerged as a powerful approach for directly evaluating reaction mechanisms and selectivity in transition metal-ligand complexes involving organometallic intermediates. Density functional theory (DFT) quantum mechanical methods enable the generation of potential energy surfaces and structures that define reaction mechanisms and allow for the evaluation of selectivity through statistical transition state theory. However, in certain cases, it is necessary to go beyond statistical treatments and incorporate atomic motion through molecular dynamics simulations. Additionally, many transition metal-mediated reactions involve unpaired electrons and spin state crossings. This dissertation focuses on the application of DFT-derived potential energy surfaces and molecular dynamics simulations to investigate reaction mechanisms and selectivity in transition metal-mediated processes, particularly those involving open-shell intermediates. Chapter 1 provides an overview of potential energy landscapes, statistical transition state theory, DFT, spin crossover reactions, and molecular dynamics simulations. Chapter 2 presents previously published work that combines DFT calculations and molecular dynamics simulations to elucidate selectivity in a spin crossover reaction between a bisphosphine iron complex and ethylene, originally published in Chemical Science, 2023, 14, 9400-9408. Chapter 3 details DFT potential energy surface calculations and molecular dynamics simulations for metal-hydride hydrogen atom transfer (MHAT) reactions with alkenes. Chapter 4 compiles previously published studies involving potential energy surface calculations for nickel-catalyzed electrochemical cross-coupling reactions. This compilation includes collaborative experimental-computational research published in Angewandte Chemie International Edition, 2023, e202403844; Faraday Discussions, 2023, 247, 132-142; and Angewandte Chemie International Edition, 2024, e202407118. The appendix provides methodological details related to molecular dynamics simulations across multiple spin states and the explicit solvent setup used in these studies.

Degree

PhD

College and Department

Computational, Mathematical, and Physical Sciences; Chemistry and Biochemistry

Rights

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