Digital Commons Network^™

Net Carbonyl Ene Reactions Of Olefins With Aldehydes, Alexandra Mock

Honors Theses

Aldehydes and olefins react in the presence of base and TMSOTf to yield homoallylic alcohols. In this net ene reaction, TMSOTf acts as a Lewis acid to activate the aldehyde, leading to a strong oxygen-silicon bond that acts as a driving force in the reaction. In the proposed mechanism, the α-methylstyrene attacks the carbonyl carbon of the TMSOTf-activated aldehyde to produce a carbocationic intermediate. Elimination using a relatively bulky base (2,6-lutidine) provides the homoallylic alcohol. This reaction has proven robust in terms of the aldehyde and olefin scope.

Photo And Spatial Control Of Rna Structures And Functions: Exploring Positional Effects And Photo-Responsiveness Of Azobenzene Modified Nucleotides, Jinxi Du

Electronic Theses & Dissertations (2024 - present)

RNA molecules perform many important biological functions by forming complex three-dimensional structures stabilized by base pairing, tertiary interactions, and metal ion coordination. Because RNA function depends strongly on its structure, methods that allow reversible control of RNA conformation and activity are important for understanding RNA behavior and for potential therapeutic applications. However, achieving reversible and site-specific control of RNA structure, especially at the single-nucleotide level, remains challenging. In this dissertation, I developed and applied azobenzene-modified nucleotides as a chemical tool to enable optical and spatial control of RNA structure and function.

The first part of this dissertation focuses on establishing …

Repeatability And Reproducibility Of Likelihood Ratio Estimation For Forensics Using Machine Learning: An Application To In-Silico Fire Debris Data, Cameron Ezazi

Graduate Studies Theses and Dissertations 2026

The importance of using statistical evidence to help inform the interpretation of forensic evidence has grown greater over time. This is especially evident in the field of forensic fire debris analysis, where the reliability and reproducibility of statistical results are crucial. This thesis investigates how the application of 5 different common machine learning methods on an in-silico fire debris dataset can be reduced to a univariate forensic score to create score-based likelihood ratios (SLRs), and how these ratios should be interpreted. These SLRs are crucial in supporting or rejecting a Prosecutor’s or Defense’s hypothesis, thus making the previously mentioned reliability …

Fumigant Toxicity Of Essential Oils From Chemotypes Of Curry Tree (Murraya Koenigii) Against Adult African Malaria Mosquito (Anopheles Gambiae Sensu Stricto), Clarence M. Mang’Era, Fathiya M. Khamis, Ahmed Hassanali, Paul O. Mireji

All Peer-Reviewed Publications

The toxicity of fumigant formulations of essential oils (EOs) from curry tree (Murraya koenigii (L.) Spreng (Rutaceae)) against African malaria adult mosquito (Anopheles gambiae sensu stricto (Giles, 1902) (Diptera: Culicidae: Culicini)) was evaluated to identify most effective chemotype of the curry tree against the mosquitoes. Ninety-two compounds (91.78%–96.47% coverage) in the EO profiles were identified, among which EO isolated from curry tree chemotype from Kibwezi was most toxic. This chemotype had a median lethal dose (LD50) of 3.6 × 10⁻³ mg/cm³ (95% CI: 2.70–4.58) and a lethal time (Ti50) of 1.91 ± 0.086 h (p < 0.001). The equivalent LD50 of EOs of chemotypes from Mombasa, Makindu, and Malindi in Kenya was 4.9 × 10⁻³, 6.6 …

Evaluation Of A Novel Re-Crosslinkable Preformed Particle Gel For Conformance Control In Ultra-High Temperature Reservoirs, Yanbo Liu, Tao Song, Caleb Kwasi Darko, Thomas P. Schuman, Mingzhen Wei, Baojun Bai

Chemistry Faculty Research & Creative Works

Preferential fluid flow remains a major challenge in subsurface energy production and gas storage operations, resulting in excessive water production in mature oil fields, reduced heat extraction in geothermal reservoirs, and low sweep and storage efficiency in CO₂-EOR projects. Polymer gels are widely used to mitigate high-permeability channels; however, conventional systems exhibit limited plugging efficiency and short lifetimes in ultra-high-temperature reservoirs due to poor thermal stability. This study presents a novel ultra-high-temperature-resistant preformed particle gel (UHT-PPG) developed for conformance control in reservoirs with temperatures of 150–275 °C and severe super-K or channeling problems. The material was evaluated in …

Progression Toward Terminal Oxidation Of Starch Via Hybrid Organic–Enzymatic Bioanode For Renewable Carbohydrate Conversion, Adam Milam, Jose Intano, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

The performance of starch-based biofuel cells is fundamentally limited by inefficient utilization of the fuel's inherent energy density. Sequential oxidation of carbohydrate fuels, such as glucose, the monomeric unit of starch, using minimal catalyst systems has therefore emerged as a promising strategy to improve biofuel cell efficiency. Here, we extend a previously reported three-catalyst, organic–enzymatic glucose oxidation cascade to polymeric carbohydrate fuels by integrating enzymatic starch depolymerization with downstream electrochemical oxidation. To our knowledge, this represents the first demonstration of a defined hybrid organic–enzymatic cascade designed to drive progression of starch-derived glucose equivalents toward terminal oxidation using a minimal catalyst …

Multi-Isotope Tracing Reveals Nitrate And Sulfate Sources And Fate Across Contrasting Activity Zones In A Semi-Arid Basin Of Northern China, Chang Yue, Ruizhong Gao, Limin Duan, Tianke Su, Xixi Wang, Tingxi Liu, Guoqiang Wang

Civil & Environmental Engineering Faculty Publications

In semi-arid surface water-groundwater systems, nitrate (NO₃^–) and sulfate (SO₄²^–) are jointly influenced by natural processes and anthropogenic activities, yet how their sources, transformations, and export vary across contrasting activity zones remains insufficiently understood. Integrating hydrochemistry, multiple stable isotopes, a Bayesian isotope mixing model, and representative-section flux analysis, this study investigated the source compositions, transformation processes, and export differences of NO₃^– and SO₄²^– in the Dahei River Basin.   New hydrological insights for the region: Results showed greater SO₄²^– enrichment in high-activity zones, whereas NO₃^– exceedance was more prominent in low-activity zones. In …

Characterizing The Unique Chemical Imprint Of On-Axis, Lower-Temperature Hydrothermal Flow To The Deep Ocean (Southern East Pacific Rise, 16.5°-18.0°S), Laura E. Moore, Randelle M. Bundy, Joseph A. Resing, Scott White, Tamara Baumberger, Peter N. Sedwick, Nathaniel J. Buck, Anson M. Antriasian, Isaac Keohane, Bettina M. Sohst, Sharon L. Walker, Christopher R. German

OES Faculty Publications

In addition to high-temperature vents, lower-temperature flow (LTF) (< 300°C) is abundant along mid-ocean ridges and contributes globally-important fluxes of heat and water along with largely-unconstrained geochemical influences on the ocean. We examined the impact of on-axis LTF on the chemical composition of the overlying water column (< 40 m above seafloor) along the 16.5°-18.0°S sector of the ultrafast-spreading southern East Pacific Rise using autonomous underwater vehicle Sentry surveys and conductivity-temperature-depth rosette casts. LTF sites were typically spatially isolated from high-temperature systems and imparted unique chemical signatures to the overlying ocean. Water column samples impacted by LTF exhibited low particulate iron:sulfur ratios and high methane: total-dissolvable manganese ratios, whereas samples influenced by high-temperature venting exhibited opposite trends. We confirmed that LTF imparts a distinct and measurable chemical signature to the water column, independent from high-temperature vents. Isolated, on-axis LTF will be important to consider when assessing hydrothermal circulation impacts upon ocean biogeochemistry.

Testing The Limits Of Provenance Analysis From Basaltic Fluvial Sediment Near Sandvatn, Iceland, As A Mars Analog, Audrey R. Putnam, Kirsten L. Siebach, Michael T. Thorpe, Valerie M. Tu, Elizabeth B. Rampe, Candice C. Bedford, Gelu Costin, Joseph J. Tamborski

OES Faculty Publications

Detrital sediments that accumulate downstream and are preserved in sedimentary rocks can allow characterization of geologic formations that are inaccessible for spatial or temporal reasons. However, mixing, sorting, and alteration of sediment during transport may complicate reconstruction of protolith characteristics. We test the preservation of three key provenance signals in coarse fluvial sand at a Mars analog watershed in Iceland to determine whether detrital sediments capture (a) watershed magmatic chemical variation, (b) textural indicators of lava-water interaction during eruption and cooling, and (c) hydrothermal alteration. Specifically, we tested whether diagnostic variations in rock mineralogy, chemistry, and texture can be recovered …

Re-Crosslinkable Hyper-Branched Polymer Gels Based On A Transamidation Reaction, Tao Song, Baojun Bai, Thomas P. Schuman

Patents

The present invention generally relates to the field of conformance control in oil fields, particularly to a re-crosslinkable preformed particle gel system, and composition thereof. The composition of the re-crosslinkable preformed particle gel system contains monomers, crosslinkers, a polymer matrix, and additives. Components in the composition for re-crosslinkable preformed particle gel in the present invention have excellent compatibility with each other, and the obtained gel has excellent long term high-temperature resistance property. Different from prior products, in the recrosslinkable preformed particle gel compositions according to embodiments of the present invention, the components that are used to re-crosslink the particle gels …

Bio-Orthogonal Chemistry-Based Strategy To Turn-On And Turn-Off Crispr-Cas9 Gene Editing In Solution And In Live Cells, Bhoomika Pandit

Electronic Theses & Dissertations (2024 - present)

The CRISPR–Cas9 system is a widely popular tool for genome engineering. There is a strong interest in developing tools for temporal control of CRISPR-Cas9 activity to address some of the challenges and to broaden the scope of potential applications. In this thesis I describe two biorthogonal based approaches to either Turn-ON and Turn-OFF CRISPR-Cas9 gene editing.

In first project work I describe a bio-orthogonal chemistry-based approach to Turn-ON Cas9 nuclease activity with temporal precision. We report a TCO-acylimidazole reagent that acylates 2′-OH groups of RNA. Poly-acylation (“cloaking”) of RNA was optimized in vitro using a model 18-nt oligonucleotide, as well …

Investigation Of Fine-Grain Cu And Cu Alloys For Low-Temperature Hybrid Bonding Applications, Sarabjot Singh

Electronic Theses & Dissertations (2024 - present)

Hybrid bonding has emerged as a key enabler for next-generation three-dimensional (3D) integration, offering fine-pitch interconnects and improved electrical performance. However, conventional Cu–Cu hybrid bonding typically requires elevated temperatures to achieve sufficient diffusion and interface quality, posing challenges for temperature-sensitive device integration and process compatibility. This work investigates materials engineering approaches to enable low-temperature Cu–Cu bonding through both microstructure design and alloying strategies.

This work begins by examining grain refinement in Cu as a pathway to enhance diffusion through increased grain boundary density, providing efficient atomic transport without introducing additional elements. Three Cu-based systems Cu–Co, Cu–Ag, and Cu–Al were systematically …

The Chemistry Of Red Lipstick: The Impact Red Lipstick Has On Society, Lilliana Weldeslassie

Electronic Theses & Dissertations (2024 - present)

Cosmetic chemistry is deeply embedded in everyday life, shaping the products people use from morning to night. Among these, red lipstick stands out as a formulation that blends complex chemistry with a cultural meaning. This thesis examines the scientific foundations of red lipstick through its chemical composition, pigment structure, toxicological history, analytical methods, and evolving sustainability practices. Historically, red lipsticks relied on high-risk ingredients such as lead, mercury, and other toxic metals, reflecting an era before chemical safety and regulatory oversight were incorporated.²¹ Modern formulations have established safer synthetic dyes, natural waxes, plant-based oils, and stabilizers created to optimize …

Development Of Photolabile Coumarin Linker For Rna Synthesis And Crisprcas9 Applications, Ian Mcclain

Electronic Theses & Dissertations (2024 - present)

The scope of RNA-based therapeutics continues to expand as more siRNA, mRNA, and CRISPR-based treatments are approved for various medical applications. Purification of synthetic RNA drugs is inherently challenging and requires considerable time and resources. New cost-effective and efficient purification strategies will expedite drug development process and will lower the drug costs. In this thesis I describe two generations of photolabile linkers for the non-chromatographic purification of therapeutic RNAs. In addition, the photolabile linker was utilized for regulation CRISPR-Cas9 gene editing. In the first part of the thesis, I describe the first generation of the photolabile coumarin-based linker for non-chromatographic …

Improving Modeling Of Corrosion Products In The Primary Circuit Of Light Water Reactors Through The Experimental Determination Of Crud Characteristics, Sri Saravana Konganapuram Narasimma Bharathi

Electronic Theses & Dissertations (2024 - present)

High-temperature water flowing through the coolant circuits in pressurized water reactors (PWRs) creates a harsh environment, deteriorating these materials. This corrosion results in the formation of oxide layer(s) primarily composed of nickel ferrites, iron oxides, nickel oxides, and other nickel-iron-chrome spinel oxides. Being exposed to fluid with high flow rates and pressure, these oxide layers can be eroded, resulting in particulate fouling due to the release of corrosion products (Chalk River Unidentified Deposits, CRUD) into the coolant circuit. When CRUD subsequently deposits on fuel surfaces, it negatively affects the fuel performance (heat transfer and fuel failure); in addition, the particles …

Swimming In Uncertainty: Filling Data Gaps And Providing An Educational Platform For Beach Water Quality At Tybee Island, Georgia, Lukas Roberson

College of Graduate Studies: Theses & Dissertations

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Swimming in beaches water contaminated with high levels of bacteria can make you sick. Current monitoring at the public beaches on Tybee Island consists of weekly monitoring and enumeration of fecal indicator bacteria that takes 24 hours for results. If the number of bacteria exceed regulatory limits, a public health advisory is issued, and affected waters are retested until …

Flexible Membrane Electrodes For Use In High-Capacity Lithium-Ion Batteries, David A. Denemark

College of Graduate Studies: Theses & Dissertations

Wearable electronic devices require high-capacity flexible batteries to improve user comfort and increase usage time per charge. In this thesis, flexible lithium-ion battery (LIB) electrodes are prepared using a novel and scalable phase inversion method, embedding one-dimensional SnO₂ nanowires and double-walled carbon nanotubes within a porous polyacrylonitrile asymmetric membrane. The optimized electrode delivered an initial specific discharge capacity of 915.93 mAh g⁻¹, approximately 2.5 times greater than conventional graphite anodes, with 61.99% capacity retention after 45 cycles. The incorporation of a carbon mesh substrate further enhanced both electrochemical and mechanical performance, achieving 89.46% capacity retention after 45 cycles and a …

Application Of Organic Geochemistry To The Characterization Of Hydrochar And Biochar: Insights Into Composition And Optimization, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Rubén Forján, José Luis Gallego

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Hydrothermal carbonization has garnered significant attention in recent studies due to potential applications of the hydrochar produced, which overlap with those of torrefied biochar, including soil improvement, carbon sequestration, and energy production. However, unlike the relatively uniform properties of biochar, hydrochar characteristics can vary greatly depending on the feedstock used. Advanced characterization techniques are essential to better understand these materials and enhance their practical applications. Research on hydrochar requires a multi-faceted approach, including molecular-level studies, to optimize production processes and identify specific applications.

In this regard, analytical methods commonly used in organic geochemistry could play a crucial role in deepening …

Synthesis Of The Naga(S1−Xsex)2 Solid Solution From Mechanically Activated Precursors, Louisiane Verger, Julien Trébosc, Santhoshkumar Sundaramoorthy, Amitava Choudhury, Olivier Hernandez, Eric Furet, Sébastien Chenu, David Le Coq, Laurent Calvez, Olivier Lafon

Chemistry Faculty Research & Creative Works

NaGaS₂ and NaGaSe₂ are two recently discovered compounds that crystallize in the same structure type. In this work, NaGa(S_1−xSe_x)₂ (x = 0.5, 0.75 and 1) are prepared using an alternative synthesis route, mechanochemistry followed by heat treatment. Na₂S, Na₂Se, Ga₂S₃ and Ga₂Se₃ are milled in stoichiometric proportions. Differential scanning calorimetry, X-ray diffraction and solid-state nuclear magnetic resonance (²³Na and ⁷¹Ga) show that the compounds after milling are composed of crystalline NaGa(S_1−xSe_x)₂ with an amorphous part. …

Basis Design For Electronic Structure And Beyond, Weishi Wang

Dartmouth College Ph.D Dissertations

At the intersection of quantum physics, quantum chemistry, and materials science, electronic structure is the study of electrons in solid-state and molecular systems. Electronic-structure computation relies on discretizing the many-electron Hamiltonian with a finite single-particle basis set. However, basis-set construction is conventionally treated as an ad hoc preprocessing step. This thesis develops an expressive and flexible framework for active, system-oriented basis-set design and numerical modeling strategies that treat basis functions as tunable representations to encode electronic ground-state information.

We first introduce a multi-layered, differentiable basis-construction framework that embeds a set of primitive parameters into mixed-contracted Gaussian-type orbitals. We then develop …

Monomeric And Dimeric Metal Complexes Of A New Tridentate Azole-Isoindoline-Urea Ligand, Ben Hudak

Williams Honors College, Honors Research Projects

1,3-Diiminoisoindoline (DII) compounds have been found to be novel materials for both metal binding and chromophore applications. In this work, I am investigating the next synthetic step in developing pyrazole- and indazole-DII compounds. These compounds stem from the reaction of the unsubstituted imine of the pyrazole- or indazole-DII adduct with an isocyanate. These DII compounds, DII-pyrazolePhNCO, DII-pyrazolenapthylNCO, DII-indazolePhNCO, DII-indazolenapthylNCO, DII-pyrazoleptolylNCO, and DII-indazoleptolylNCO were prepared using ethanol as the solvent and heat. Metal acetates were then reacted with the ligands using DMF and heat. The acetate salts included copper (II) and nickel(II). Some distinctive hydrogen bonding interactions were observed in the …

Identification Of Modified Polymer End Groups For Correlations To Physical Properties, Tj Sacco

Williams Honors College, Honors Research Projects

Plastic has become the primary material for containers in both industrial and commercial fields. Plastics are the optimal choice since they have many physical properties that make them ideal candidates: durability, heat resistance, chemical stability, as well as their inexpensive production cost. Nowadays, the desire for more versatile plastics with strength, flexibility, hydrophobicity, and biodegradability has grown; however, concerns for plastic use have started to rise as well. The overuse of plastics poses a threat to the environment and people’s health: plastics are hard to break down completely which results in the formation of micro(nano)plastics (MNPs). In attempts to circumvent …

Computer-Aided Molecular Design To Identify More Environmentally Friendly Pfas, Melvin M. Keita

Williams Honors College, Honors Research Projects

The goal of this project is to inversely design alternatives to per- and polyfluoroalkyl substances (PFAS) using Computer-Aided Molecular Design (CAMD). PFAS, also described as “forever chemicals”, have been used in industry and consumer products since the 1940s. PFAS can be found in drinking water, food, food packaging, waste sites, and other sources. Exposure to different PFAS can lead to increased risks of some cancers, immune effects, and reproductive effects. Pulling from existing data, this project will use quantitative structure-property relationships (QSPRs) to design PFAS alternatives that possess optimal properties to prevent adsorption into drinking water and other potential sources …

Using Nmr Spectroscopy And Linear Discriminant Analysis To Molecular Profile Varietal Honey, Taylor Mac

Master's Theses and Doctoral Dissertations

In recent years, varietal honey has been a massive target of adulteration through mislabeling and the addition of other sugars. Unethical companies do this to cut production costs while still charging the consumer full price. Previous studies have used nuclear magnetic resonance (NMR) to unravel possible adulteration in honey, but currently, there are no standard rapid methods to authenticate varietal honey. In our research, we collected NMR signatures (“fingerprints”) and combined them with linear discriminant analysis (LDA) to predict the varietal, country, and region of varietal honey. As a part of the project, we investigated whether an adjustment to the …

Schiff Bases As Versatile Platforms: From Multinuclear Dysprosium Complexes To Halogen-Mediated Quasiracemic Crystal Engineering, Macy M. Michorczyk

Theses and Dissertations

Understanding the factors that govern molecular assembly is fundamental in both coordination chemistry and crystal engineering. This thesis investigates these processes through two studies that employ single-crystal X-ray diffraction to elucidate the structural principles underlying the formation of multinuclear metal complexes and the crystal packing of quasiracemates.

The first study examines the unexpected formation of multinuclear metal complexes. Structural characterization of a series of dysprosium complexes was used to compare molecular architectures and identify structural relationships that support a proposed pathway of formation. These findings shed insight into the assembly process that may have lead to their formation.

The second …

Concerted Proton Transfer In Homogeneous And Heterogeneous Cyclic Hydrogen-Bonded Clusters Of H2o, Hf, And Hcl, Max R. Tucker, Yuan Xue, Nathan R. Speake, Eden Nickolson, Jeremy M. Carr, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

This work examines various homogeneous and heterogeneous clusters of hydrogen-bonded (HF)x(H₂O)y(HCl)z complexes, where x + y + z = 3 or 4. For each unique cyclic structure associated with the xyz permutations, the geometries of the reactant, product, and transition state (TS) for concerted proton transfer (CPT) were fully optimized using second-order Møller-Plesset perturbation theory (MP2) with a mixed basis set consisting of cc-pVTZ for H atoms and aug-cc-pVTZ for O, Cl, and F atoms (denoted haTZ). Harmonic vibrational frequencies were also computed at the same level of theory to verify the nature of the stationary points. Intrinsic …

Volatile Organic Compound Analysis Of Humboldt Penguin (Spheniscus Humboldti) Preen Oil: A Pilot Study, Dante E. Rojas, Mitchell M. Mccartney, Eva Borras, Michael O. Eze, Abigail Pietrow, Jennifer J. Valvo, Cristina E. Davis

Chemistry Faculty Research & Creative Works

Avian olfaction has gained prominence in recent decades for its roles in social communication and behavior. In penguins, the chemical characterization of preen oil remains limited. In this exploratory study, we characterized the volatile organic compound (VOC) profile of preen oil from Humboldt Penguins (Spheniscus humboldti). Preen oil from 12 captive individuals was analyzed using headspace sorptive extraction (HSSE) coupled to gas chromatography–mass spectrometry (GC–MS). Chemometric analyses examined variation in VOC profiles by sex, age class, and breeding activity. We detected 54 compounds (20 tentatively identified), including linear alcohols, methyl ketones, carboxylic acids, saturated hydrocarbons, oxygenated and nitrogen-containing organics, prenolipids, …

Soft-Chemical Scalable One-Pot Aqueous-Medium Synthesis Of Na3(Vo)2(Po4)2f-Based Cathodes: Compositional Tuning And Electrochemical Performance In Na- And Li-Ion Batteries, Prashanth Sandineni, Subal Chandra Manna, Sutapa Bhattacharya, Santhoshkumar Sundaramoorthy, Ramesh Deokate, Milad Aghayi-Anaraki, George E. Sterbinsky, Kartik Ghosh, Amitava Choudhury

Chemistry Faculty Research & Creative Works

One of the most important cathode materials for Na-ion batteries, Na₃(VO)₂(PO₄)₂F, and its compositional variants have been synthesized using four different and facile one-step soft chemical routes. The as-synthesized compounds, Na_2.95(VO)₂(PO₄)₂F (I), Na_2.93(VO)₂(PO₄)₂F (II), and Na_2.58(VO)₂(PO₄)₂F (IV), crystallize in the tetragonal crystal system in the P4₂/mnm space group, while Na₃(VO)₂(PO₄)₂F (III) crystallizes in the orthorhombic crystal system in …

Deciphering Ultrafast Photoinduced And Photocatalytic Reaction Dynamics On Oxide Surfaces: Direct Detection Of Radical Intermediates, Fragment Trapping, And Carbon–Carbon, Carbon–Oxygen, And Carbon–Hydrogen Bond Formation Pathways, Aakash Gupta

Graduate Studies Theses and Dissertations 2026

Understanding photoinduced reactions at solid interfaces is essential for advancing heterogeneous photocatalysis, surface photochemistry, and energy conversion technologies. This dissertation investigates the ultrafast dynamics of reactive intermediates, fragment trapping, and radical-mediated bond formation on oxide surfaces using time-of-flight mass spectrometry in conjunction with femtosecond pump-probe spectroscopy. Various experimental findings are validated through collaborations via density functional theory (DFT). By combining temporal, mass, and energy-resolved measurements, this work provides molecular-level insight into the elementary processes governing light-driven surface reactions. The photodissociation dynamics of CH₃I adsorbed on TiO₂(110), TiO₂(100), and amorphous silicon oxide surfaces are examined …

A Theoretical Study Of Molecular Photoionization: Applications To Molecules Of Astrophysical And Atmospheric Interest, Conner Penson

Graduate Studies Theses and Dissertations 2026

This thesis is devoted to the development of the model for total molecular photoionization spectra which is general to diatomic molecules and the application of this model to two benchmark systems, CH and N2, for verification. This model combines multi-channel quantum defect theory, first-principles ab initio molecular calculations, and vibrational frame transformation to accurately model molecular photoionization and electron impact including vibrational dynamics. The scattering data and transition dipole moments for the molecular systems were calculated using R-matrix method through the UKRMol+ codes. A vibrational frame transformation is then performed and multi-channel quantum defect theory is used to calculate closed …