Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Institution
Articles 1 - 5 of 5
Full-Text Articles in Computational Chemistry
Computational And Experimental Investigation Of Elemental Sulfur And Polysulfide, Jyoti Sharma
Computational And Experimental Investigation Of Elemental Sulfur And Polysulfide, Jyoti Sharma
Dissertations
Petroleum processing results in the generation of significant quantities of elemental sulfur (S8), leading to a surplus of sulfur worldwide. Despite its abundance and low cost, the use of sulfur in value-added organic compound synthesis is limited due to its unpredictable and misunderstood reactivity. This dissertation aims to address this issue by tackling it from two angles. Firstly, by utilizing Density Functional Theory (DFT) calculations, the reactivity of sulfur in the presence of nucleophiles is studied. This facilitates the identification of organic polysulfide intermediates that can be generated under different conditions, as well as the corresponding reactivity for …
Advances In One-Electron Self-Interaction-Correction Methods For Accurate And Efficient Self-Interaction-Free Density Functional Calculations, Selim Romero
Open Access Theses & Dissertations
Density functional theory (DFT) is a widely used computational method for studying electronic structures of atoms, molecules, and solids. It provides an exact theory for obtaining ground state energy from the ground state density. However, since the exact exchange-correlation functional remains unknown, approximate exchange-correlation functionals called approximate density approximations (DFAs) are used. The foundation of many DFAs is the local spin density approximation (LSDA). It serves as the starting point for constructing various DFAs. However, DFAs are prone to self-interaction errors (SIE) due to the improper cancellation of the approximate exchange energy and the Coulomb energy. This issue impacts the …
Isolating The Electronic Effects Of Systematic Twist In Highly Substituted Aromatic Hydrocarbons Using Density Functional Theory, Grace Tully, Emily A. Jarvis
Isolating The Electronic Effects Of Systematic Twist In Highly Substituted Aromatic Hydrocarbons Using Density Functional Theory, Grace Tully, Emily A. Jarvis
Honors Thesis
Density functional theory (DFT) was employed to investigate dodecaphenyltetracene as well as similar molecules containing differing backbone lengths and electron withdrawing groups with interest in manipulating the twist to lower the LUMO level for increased electron mobility. Optimization and frequency time-independent calculations followed by time-dependent (TD-DFT) energy calculations were performed at the B3LYP/G-311G level of theory to analyze electronic trends as a result of increased backbone length and consequently distorted end-to-end molecular twist. These calculations demonstrate a linear relationship with negative slope between the estimated HOMO-LUMO, fundamental, and optical gaps as a function of the number of fused rings along …
Predicting The Reactivities And Reaction Mechanisms Of Photochemically Produced Reactive Intermediates, Benjamin Barrios Cerda
Predicting The Reactivities And Reaction Mechanisms Of Photochemically Produced Reactive Intermediates, Benjamin Barrios Cerda
Dissertations, Master's Theses and Master's Reports
Photochemically produced reactive intermediates (PPRIs) such as the hydroxyl radical, carbonate radical (CO3•-) singlet oxygen (1O2) and triplet state of chromophoric dissolved organic matter (3CDOM*) are formed in sunlit natural waters upon photoexcitation of chromophoric dissolved organic matter (CDOM). PPRIs react with the organic compounds involved in key environmental processes, resulting in transformation products of smaller molecular weight than their parent compounds. Photochemical transformation of these key water constituents due to their reactions with PPRIs may pose potential effects on human and aquatic ecosystems. Consequently, there is a need …
The Future Of Alternative Energy? Simulating Methyl Stearate Pyrolysis Via Molecular Dynamic Processes, Sarah J. Adeoye
The Future Of Alternative Energy? Simulating Methyl Stearate Pyrolysis Via Molecular Dynamic Processes, Sarah J. Adeoye
MSU Graduate Theses
The process of extracting and refining crude oil is both expensive and environmentally hazardous. The synthesis of biodiesel sourced from vegetable oils is a renewable process and less hazardous to the environment. Therefore, we seek to understand the pyrolysis procedure at an atomic level in hopes of optimizing future fuel viability. Herein, I analyze methyl stearate (a component of biodiesel) using an in-house database of ab initio trajectories, each simulating 1.0 ps (with 1.0 fs resolution). These jobs were observed for significant bond-breaking/forming events, the type of fragments produced, and the exact position and time for each event. Statistical analysis …