CHEM Theses and Dissertations

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This collection includes digital copies of master's theses and dissertations (ETD) completed in the Department of Chemistry. The ETD collection has been started in 2005.

A full set of the WSU theses and dissertations may be found at the University Libraries stacks (Call No.: LD2667.T4 A-Z for Master's Theses and LD2667.T42 A-Z for Dissertations) and in Library Special Collections.

Search Libraries Catalog for theses and dissertations bibliographic description, including student and his/her advisor's name, title of work, abstract, links to other digital holdings if available, etc.

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Now showing 1 - 5 of 126
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    An investigation into cyano substituted polypyrazolylborate complexes of palladium, platinum and iron
    (Wichita State University, 2023-12) Oberley, Alan Joseph; Eichhorn, David M.
    Polypyrazolylborates, also known as scorpionates, have been important ligands in inorganic chemistry since their introduction in the 1960s by Trofimenko. Our research group has been working with cyanopyrazoles, which have a CN subsituent in the 4-position, and alkyl or aryl substituents at the 3-position, or 3-and 5-positions. Reactions of palladium and platinum with Tp and Bp scorpionates have produced pyrazole complexes of interest, which were subsequently synthesized rationally. While no scorpionate complexes were completely characterized, the pyrazole complexes give information about the effects of the cyano group on the structure of compounds, especially when compared to similar compounds without the cyano substituent. Two new iron(II) cyanoscorpionates, $(Tp^{Cypr,4CN})_2Fe$ and $(Tp^{Ethyl,4CN})_2Fe,$ were synthesized, isolated, and characterized. These complexes are the first non-isomerized iron(II) cyanoscorpionates. These both are high spin at room temperature, and appear to be high spin down to 100K. Comparison to similar non-cyano compounds gives insight to the effect of the CN substituent on the structural, magnetic, and electronic properties.
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    Computation of Phosphorus-31 NMR chemical shifts of nickel complexes using density functional theory
    (Wichita State University, 2023-12) Steinert, Ryan M.; Mitchell-Koch, Katie R.
    The largest density functional theory benchmark study, to date, of calculated $^{31}P$ chemical shifts of phosphorus-containing ligands in nickel(0), nickel(II), and nickel(I) complexes is presented. Calculated shifts are directly compared to experiment. Many of these complexes are synthetically useful and on the cutting edge of rational catalyst design. Excellent results are obtained for the set of 56 nickel(0) complexes, with a root mean square error (RMSE) of 6 ppm. This result is obtained by computing the isotropic shielding at the PBE0/cc-pVTZ//PBE0/6- 31+G(d) level; the continuous set of gauge transformations (CSGT) is utilized to address the gauge problem and triphenylphosphine is used as the reference. Integration grid size does not affect the accuracy of shielding calculations, and the SG1 grid (50 radial shells, 194 angular points per shell) in the Gaussian program may be utilized to save time. This new method for nickel(0) complexes offers the following advantages over two methods recently published in Organometallics: a larger data set (n = 100 vs. n = 72 and n = 18), use of a single reference compound, no linear scaling factors are needed, and purely electrostatic solvation models and mixed basis sets are avoided. For the set of 33 nickel(II) complexes, reasonable results are obtained (RMSE = 16 ppm, n = 40) using the following scheme: PBE0/6-311++G(d,p)//PBE0/6-31+G(d) with CSGT and phosphoric acid as the reference. For the set of 13 nickel(I) complexes, the computation scheme used for nickel(0) complexes yields an RMSE of 16 ppm if one outlier (complex D7) is excluded (n = 12). It is unclear why better results for nickel(II) and nickel(I) complexes are not obtained. Single point energy calculations show the singlet state to be lower in energy for all nickel(II) complexes under investigation. The singlet state nickel(II) complexes were screened for multireference character by examining Etriplet – Esinglet (ΔE) and the HOMO-LUMO energy gap as recommended in the literature; no evidence of multireference character was found.
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    Innovative approaches to enhance student learning in chemistry laboratories: An independent study conducted in three distinct parts on solvatochromism, virtual reality and python programing applications
    (Wichita State University, 2023-12) Shahryari, Elaheh; Mitchell-Koch, Katie R.
    This dissertation is a three-component exploration into educational strategies aimed at enhancing student engagement and learning in chemistry courses. The first chapter proposes that we can significantly enhance students' understanding of complex phenomena such as solute-solvent interactions and solvatochromism. Utilizing the theoretical results and engaging in detailed experiments, students are anticipated to observe changes in the UV-Vis spectrum, vibrations frequency from FTIR and bond length of the carbonyl group (C=O) due to varying solvent polarities for Betanine 30 (B30) and Michler's Ketone (MK). The second chapter of this dissertation delves into the potential of Virtual Reality (VR) as an innovative approach to improve learning outcomes in chemistry lab experiments. In the process, we assess VR's effectiveness as a learning tool compared to traditional 2D video and conventional teaching methods to enhance comprehension of the titration process, increased confidence in burette reading, and improved accuracy in ascertaining the concentration of an unknown HCl solution. Chapter three of this dissertation focuses on coding programming to undergraduate students in physical chemistry classes. We believe that Python will help students understand programming better and use it for data analysis and visualization. We hope to see students get a deeper understanding of complex chemistry concepts, build their confidence, and answer difficult questions, like those about the Schrödinger equation. Ultimately, we believe that if students perform better on ACS exam questions, it shows that our teaching methods are effective in helping students understand complicated chemical concepts.
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    Acetohydroxamate complexes of some divalent metal ions
    (Wichita State University, 1958-06) Hitchcock, Robert; Christian, Robert V.
    Studies of the stabilities of the metal complexes of acetohydroxarnic acid have been limited to those of iron(III) (1,6) and copper(II) (8) . The present investigation was undertaken in an attempt to establish the relative stabilities of the acetohydroxamate complexes of some divalent metal ions. Jannik Bjerrwn’s (2) well- known titration method seemed to be best suited for this study.
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    Development of analytical protocols for rapid analysis of biological samples with flow-gated capillary electrophoresis
    (Wichita State University, 2023-07) Zhang, Ning; Gong, Maojun
    With the development and improvement of the whole society, people are paying more attention to their health and the protection of the environment, which requires researchers to consider better identification and detection methods for various molecular species. Capillary electrophoresis (CE) and related technologies have been used in the separation, detection, and identification of many organic and inorganic compounds for the past dozens of years because of the advantages of CE, like short analysis time and high separation efficiency. Also, numerous detectors and interfaces can be combined with CE due to the excellent adaptability in order to enhance the performance of detection sensitivity, e.g., laser-induced fluorescence (LIF), mass spectrometry (MS), and electrochemical detection. This thesis is to discuss the determination of essential biomarkers in biological samples on the flow-gated CE-LIF system. It first reports a rapid and sensitive method with the flow-gated CE-LIF system to determine collagen degradation products, including proline, hydroxyproline, and other prolyl dipeptides in human urine samples, which is suited for the early diagnosis of collagen-related diseases. Experimental results prove that this method was capable of the separation and determination of prolyl compounds with good reproducibility, accuracy, sensitivity, and robustness. Second, the utilization of solid-phase extraction (SPE) in the purification and concentration of catecholamines (CAs) highlights the effectiveness of this method as a sample pre-treatment technique for catecholamines in real samples. By effectively removing interfering compounds and enhancing the concentration of the target analytes, SPE contributes to the overall reliability and accuracy of CA analysis.
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