440 Matching Results

Results open in a new window/tab.

Abelian Group Actions and Hypersmooth Equivalence Relations (open access)

Abelian Group Actions and Hypersmooth Equivalence Relations

We show that any Borel action on a standard Borel space of a group which is topologically isomorphic to the sum of a countable abelian group with a countable sum of lines and circles induces an orbit equivalence relation which is hypersmooth. We also show that any Borel action of a second countable locally compact abelian group on a standard Borel space induces an orbit equivalence relation which is essentially hyperfinite, generalizing a result of Gao and Jackson for the countable abelian groups.
Date: May 2019
Creator: Cotton, Michael R.
System: The UNT Digital Library

Allusions and Borrowings in Selected Works by Christopher Rouse: Interpreting Manner, Meaning, and Motive through a Narratological Lens

Access: Use of this item is restricted to the UNT Community
Christopher Rouse (b. 1949), winner of the Pulitzer Prize for his Trombone Concerto (1993) and a Grammy award for his Concerto de Gaudi (1999), has come to the forefront as one of America's most prominent orchestral composers. Several of Rouse's works feature quotations of and strong allusions to other composers' works that are used both rhetorically and structurally. These borrowings range from a variety of different genres and styles of works, from Claudio Monteverdi's L'incoronazione di Poppea to Jay Ferguson's "Thunder Island." Due to the more accessible filtering and funneling methods of musical borrowings (proliferation of mass media), the weighty discourses attached to them, and their variety of functions (critiquing canons, engaging in an allusive tradition, etc.), quotation has become elevated to the most prominent of musical actors that trigger narrative listening strategies, which in turn have a stronger role in the formation of narratives about music as well as narratives of music. The primary aim of this study is to adapt and apply more recent methodological narrativity frameworks to selected instrumental compositions by Rouse containing quotations, suggesting that their manner of insertion, their method of disclosure, and their referential potential can benefit from being examined through various narrative lenses …
Date: May 2019
Creator: Morey, Michael J.
System: The UNT Digital Library
American Lawn Addictions: Effects of Environmental Education on Student Preferences for Xeriscaping as an Alternative in North Central Texas, USA (open access)

American Lawn Addictions: Effects of Environmental Education on Student Preferences for Xeriscaping as an Alternative in North Central Texas, USA

Urban land use and land cover has changed in the USA, giving rise to the American lawn – manicured, resource-intensive, and non-native. Green infrastructure design has been suggested in the literature as a potential alternative to the American lawn when managed as native xeriscapes, which require little to no irrigation after establishment. Given the influence of public preference on landscaping decisions, what is the relationship between the perceived value and ecological benefits of the American lawn compared to such alternatives? Few studies have explored this question in addition to the effects of college courses on influencing student preferences, as future stakeholders, towards native xeriscapes as alternatives to the American lawn. This research measured the effects of an introductory environmental education (EE) course on measurably influencing undergraduate student preferences for four xeriscapes as alternatives to the American lawn. To measure these effects, this study utilized the perceptions of 488 students enrolled in an indirect introductory EE course and 131 students enrolled in an introductory non-EE course. Three key results emerged from this research. Students preferred the American lawn more than xeriscape alternatives, irrespective to course enrolled. Introductory non-EE did not have an effect on student preferences, whereas indirect introductory EE did …
Date: May 2019
Creator: Williams, Jared L.
System: The UNT Digital Library
An Analysis of Emma Diruf Seiler's Teaching Philosophy and Contribution to Voice Pedagogy (open access)

An Analysis of Emma Diruf Seiler's Teaching Philosophy and Contribution to Voice Pedagogy

Emma Diruf Seiler (1821-1886) was a Bavarian-American voice teacher and scientist who wrote and published Altes und Neues über die Ausbildung des Gesangorganes mit besonderer Rücksicht auf die Frauenstimme (Old and New in the Art of Singing, with Special Attention to the Female Voice) in 1861 while working in Leipzig. It was translated by William Henry Furness and published in Philadelphia as The Voice in Singing in 1868. This pedagogue and her writings are largely unknown to those who study historic bel canto pedagogy. In the opening of Seiler's pamphlet, she explained her purpose for writing was "to bring into harmony things which have always been treated separately, the Science and the Art of Singing..." Aside from brief comments in a few books on vocal pedagogy, Emma Seiler is largely unknown. Neither her contribution to voice science and pedagogy, nor the impact of her integrated philosophy on teaching have been subjected to scholarly scrutiny. The purpose of this document is to explore her philosophy on teaching, her method of female vocal instruction, and her impact on voice instruction. This dissertation historicizes evidence-based pedagogy through Seiler's example.
Date: May 2019
Creator: Sullivan, Kristen (Kristen Janell)
System: The UNT Digital Library
An Analysis of Legal Liability of Virginia Educators and School Systems (open access)

An Analysis of Legal Liability of Virginia Educators and School Systems

The doctrine of sovereign immunity in the Commonwealth of Virginia has evolved over time and the redefinition of the doctrine has been subjected to the interpretation by courts involving cases with varied facts and circumstances that have challenged the boundaries and flexibility of this legal concept. Determining the protection that a state agent was entitled to was the guiding principle in case law regarding sovereign immunity; however, understanding the purpose and intent of the doctrine of sovereign immunity was critical to determining the boundaries and criteria of the doctrine of immunity. In this dissertation, the researcher analyzed tort law as it applied to educators and public-school districts through the Virginia court system under common law and the Virginia Tort Claims Act (VTCA, 1981). The case analysis provided an overview of lawsuits heard and decisions rendered in negligence cases brought against educators and educational entities prior to and after the enactment of the Virginia Tort Claims Act in 1981.
Date: May 2019
Creator: Johnson, Tracy Lou
System: The UNT Digital Library

Animals Alive and Dead

Access: Use of this item is restricted to the UNT Community
Collection of poems.
Date: May 2019
Creator: Tieger, Leah
System: The UNT Digital Library
Annihilators of Bounded Indecomposable Modules of Vec(R) (open access)

Annihilators of Bounded Indecomposable Modules of Vec(R)

The Lie algebra Vec(ℝ) of polynomial vector fields on the line acts naturally on ℂ[]. This action has a one-parameter family of deformations called the tensor density modules F_λ. The bounded indecomposable modules of Vec(ℝ) of length 2 composed of tensor density modules have been classified by Feigin and Fuchs. We present progress towards describing the annihilators of the unique indecomposable extension of F_λ by F_(λ+2) in the non-resonant case λ ≠ -½. We give the intersection of the annihilator and the subalgebra of lowest weight vectors of the universal enveloping algebra (Vec(ℝ)) of Vec(ℝ). This result is found by applying structural descriptions of the lowest weight vectors of (Vec(ℝ)).
Date: May 2019
Creator: Kenefake, Tyler Christian
System: The UNT Digital Library
Antimicrobial and Anti-Platelet Activity in Botanical Extracts of Plants Collected in Northern Thailand (open access)

Antimicrobial and Anti-Platelet Activity in Botanical Extracts of Plants Collected in Northern Thailand

The purpose of my research work was to assess a variety of Northern Thailand plants tissue extracts for antibacterial and anti-platelet aggregation activity. The Minimum Inhibitory Concentration assay method was used to assess antimicrobial activity of plant extracts, while the Zebrafish Platelet Aggregation Assay and the in vitro Whole Human Blood Impedance Aggregation Assay were used to study anti-platelet activity. Forty one plant extracts harvested from the tissues of 26 plants collected from Northern Thailand were assessed. Thirty-four plant extracts were found to have antibacterial activity against the Gram positive bacteria Staphylococcus aureus and/or Bacillus subtilis, while six plant extracts demonstrated activity against the Gram negative bacterium, Escherichia coli. Thirteen plant extracts exhibited anti-platelet aggregation activity better than the positive control. Two crude plant extracts, twigs from Garcinia sp. and twigs from Goniothalamus chilensis were selected for fractionation. Five of the 12 fractions showed anti-platelet activity. Four fractions (two from each plant extract) were selected for further sub-fractionation. Fourteen of 35 sub-fractions were selected for further testing of anti-platelet aggregation activity with 12 sub-fractions demonstrating positive antiplatelet activity. Positive sub-fractions were analyzed using liquid chromatography-mass spectrometry to determine their chemical properties. Three compounds that possessed anti-platelet activity were characterized by …
Date: May 2019
Creator: Patcharapinyopong, Thanasan
System: The UNT Digital Library
Assessing Program-Readiness for Dental/Medical Tolerance (open access)

Assessing Program-Readiness for Dental/Medical Tolerance

Many clients with developmental and/or intellectual disabilities (ID/DD) do not tolerate routine medical or dental procedures and may require intrusive interventions, including restraint of various types (i.e. chemical, mechanical, physical, etc.) during appointments. Graduated exposure, or stimulus fading, along with reinforcement for compliance, have been shown to increase cooperation and tolerance in some clients; however, many do not respond to these types of interventions. Nine participants diagnosed with ID/DD recieved compliance/tolerance training for routine medical or dental procedures. Results of these interventions were evaluated in the context of several potential indices of readiness, such as medical diagnoses, level of disability, and presence of challenging behavior, among others. Several of the variables appeared to be correlated with program responsiveness; however, a larger sample will be necessary to draw definitive conclusions. Client characteristics and past assessments (anecdotals, preference assessments, terminal probes, and survey data) were evaluated. The analytical framework developed for this analysis may be useful to future researchers and clinicians as a model for assessing readiness for tolerance training programs.
Date: May 2019
Creator: Heath, Hayden Lee
System: The UNT Digital Library
An Assessment of Riparian Buffer Effectiveness in the Upper Hickory Creek Watershed: A GIS Approach Using the Riparian Buffer Delineation Equation (RBDE) and the Buffer Improvement Potential Percentage (BP) (open access)

An Assessment of Riparian Buffer Effectiveness in the Upper Hickory Creek Watershed: A GIS Approach Using the Riparian Buffer Delineation Equation (RBDE) and the Buffer Improvement Potential Percentage (BP)

As population increases and urbanization occurs, watershed management will be critical in the protection of water resources in North Central Texas. By 2040, Denton County will nearly double its 2010 population. The Upper Hickory Creek Watershed lies west of Denton and empties into Lake Lewisville. Lake Lewisville provides drinking water for Denton, Dallas, and other neighboring cities. Mitigation of non-point source pollutants as a result of urban and agricultural practices is essential to protecting Lake Lewisville water resources. A common best management practice used to mitigate pollutants is the protection of riparian ecotones that occupy river corridors; however, recent agricultural and urban practices are diminishing these ecosystems and their services. In this paper, the riparian buffer delineation equation (RBDE) is used to assess the current state of Upper Hickory Creek Watershed to aid in the monitoring of the riparian buffers along stream corridors. While the RBDE was used as pre-assessment tool for the riparian buffer effectiveness in the watershed, a new form of the equation was used to evaluate riparian buffer improvement potential (BP) in conjunction with Denton County parcel data to provide insights into buffer effectiveness and identify areas for improvement on a landowner scale.
Date: May 2019
Creator: Yesildirek, Monica Veale
System: The UNT Digital Library
"A Balloon Flower": A Study and Interpretive Guide to the Gagok of Jihoon Park (open access)

"A Balloon Flower": A Study and Interpretive Guide to the Gagok of Jihoon Park

Jihoon Park (b.1973), a South Korean composer with over 500 compositions spanning multiple genres, is treasured in his motherland as the most noteworthy composer of his generation. This study provides an in-depth introduction of the gagok (Korean art songs) of Park to Western teachers and students of singing, discussing his compositional techniques and their application to the interpretation of his selected songs. Moreover, the introduction to International Korean Phonetic Alphabet (IKPA) to supplement the traditionally used International Phonetics Alphabet (IPA) serves as the foundation and model for further exploration into Korean art song literature by Western scholars.
Date: May 2019
Creator: Choe, Joanne
System: The UNT Digital Library
Beyond the Binary: The Intersection of Gender and Cross-Cultural Identity in Reena Esmail's Life and Choral Works (open access)

Beyond the Binary: The Intersection of Gender and Cross-Cultural Identity in Reena Esmail's Life and Choral Works

Beyond the Binary explores the intersection of gender with cross-cultural identity in composer Reena Esmail's professional life and choral music. This intersection manifests in her musical style, which accesses the resonant spaces between Western and Indian classical music. I argue that it is through the convergence of Esmail's gender identity with her cross-cultural identity that her compositions challenge gender norms and break down perceived barriers between East and West, inviting her listeners into an intersectional feminist space. This project synthesizes musicological, theoretical, and ethnographic methods, and is meant as a starting point for choral musicians and scholars to consider cultural difference and its impact on choral music. What begins as a consideration of social themes within Esmail's life and work culminates in a practical musical analysis and performance practice guide to aid conductors in preparation of Esmail's music. The compositions discussed are I Rise: Women in Song (2016), Take What You Need (2016), TaReKiTa (2016), Tuttarana (2014), and This Love Between Us: Prayers for Unity (2016).
Date: May 2019
Creator: Pope, Lindsay (Choral conductor)
System: The UNT Digital Library

Bio-Inspired Material Surfaces with Self-cleaning, Micromanipulation and Water Collection

Access: Use of this item is restricted to the UNT Community
Geckos are famous for the skill of switchable adhesion that they use to stick on various surface while keep their fingers super clean. In the dissertation, a unique mechanism was discovered to explain gecko self-cleaning phenomena. Using atomic force microscopy (AFM), we managed to compare the microparticle-substrate adhesion and the microparticle-seta adhesion with a single seta bonded to the AFM cantilever. A dynamic effect was approved that high pulling-off speed could increase the microparticle-substrate adhesion and thus the self-cleaning appears at high moving speed. Based on the self-cleaning theory, a gecko-inspired N-doped graphene surface with switchable adhesion was achieved, which was designed into a bio-inspired micromanipulator with a success rate over 90%. When electrical bias was applied on this biomimetic surface, the charge concentration induced an electrical double layer (ELD) on the convex surfaces, which attracts polar water molecules to form a water bridge on it, significantly enhancing the adhesion on the wrinkled graphene surface, mimicking the capillary force on beetle feet. Therefore, the bio-inspired adhesive surface can be controlled with speed, electrical bias, humidity and different material surfaces. The water attraction phenomenon on the polarized surface was further tested for the potential application of water collection and evaporation in …
Date: May 2019
Creator: Wan, Yiyang
System: The UNT Digital Library
The Bobwhite Population Decline: Its History, Genetic Consequences, and Studies on Techniques for Locating and Assessing Current Populations (open access)

The Bobwhite Population Decline: Its History, Genetic Consequences, and Studies on Techniques for Locating and Assessing Current Populations

The northern bobwhite (Colinus virginianus) population decline is a severe, rangewide phenomenon beginning >150 years ago and continuing today. In this investigation, I: 1. document the timeline of bobwhite population decline and unintended genetic consequences of attempted remedies, 2) develop a model useful for predicting possible locations of potentially sustainable bobwhite populations in semiarid rangeland in Texas and Oklahoma, and 3) examine the relationship between population monitoring data and meteorological factors. While breeding season call counts of male bobwhite have been used for >70 years to provide estimates of fall populations for hunting, most studies of call counts have focused on mathematics and statistical accuracy of the count, largely overlooking the influence of meteorological factors on call counts. Here, I present the results of >4,400 individual point counts and examine their relationship with meteorological variables recorded at each stop. Humidity was positively correlated with the number of birds recorded (ρ = 0.275, p < 0.001) and temperature was negatively correlated (ρ = -0.252, p < 0.001). The number of birds recorded was significantly higher in wet years than in drought years. There was no significant correlation between wind velocity and number of birds recorded. These results suggest that, while weather …
Date: May 2019
Creator: Whitt, Jeffrey Glen
System: The UNT Digital Library
Bouncing Back: Resilience as a Moderator between Aggression and Depression in Older Gay Men and Lesbians Group Differences (open access)

Bouncing Back: Resilience as a Moderator between Aggression and Depression in Older Gay Men and Lesbians Group Differences

Older gay men and lesbians may be at greater risk for depression than older sexual majority adults due to a lifetime of sexual minority stress. We hypothesize that aggression and being single are positively associated with depression. Resilience is negatively associated with depression. Aggression, being single and resilience account for a significant proportion of variance in depression. Resilience moderates the relationship between aggression and depression. Significant differences between older gay men and older lesbians' aggression, resilience and depression scores exist. For our older gay men and lesbian combined group, a moderation analysis indicated that in addition to aggression and resilience, being single significantly predicted depression accounting for approximately 57% of the variance in depression. Furthermore, resilience significantly moderated the relationship between aggression and depression in our model of older gay men and lesbians. For our older gay men-only group a moderation analysis (indicated that and resilience significantly predicted depression accounting for approximately 57% of the variance in depression. Furthermore, resilience significantly moderated the relationship between aggression and depression in our model, in our sample of older gay men. Four our lesbian-only group a moderation analysis indicated that being single and resilience significantly predicted depression accounting for approximately 54% of the …
Date: May 2019
Creator: Griggs, Tosha
System: The UNT Digital Library
The Brazilian Art Song and the Non-Brazilian Portuguese Singer: A Performance Guide to Nine Songs by Alberto Nepomuceno (open access)

The Brazilian Art Song and the Non-Brazilian Portuguese Singer: A Performance Guide to Nine Songs by Alberto Nepomuceno

Alberto Nepomuceno (1864-1920) is considered to be the father of the Brazilian art song. With a total of seventy songs, Nepomuceno revolutionized and established a new path to the Brazilian art song. His songs were innovative because they: (1) incorporated folk elements in his songs, (2) introduced Portuguese as a language acceptable in bel canto style and (3) established Brazilian songs in the tradition of the European vanguard. His approach influenced several composers including his young student Heitor Villa-Lobos (1887-1959), one of the most significant Latin American composers. The purpose of this research is to inform singers and teachers about one of Brazil's most significant art song composers, and to provide the necessary tools--Brazilian Portuguese diction guide, IPA and poem translations of the selected songs--for effective and accurate performances and interpretations.
Date: May 2019
Creator: Riggs, Rawlianne
System: The UNT Digital Library

Brazos

Access: Use of this item is restricted to the UNT Community
Brazos is a collection of poetry that comments on and critiques life in a small town in Texas. These poems situate the speaker both in this town and in spaces removed from the town, but the work always grapples with questions of how the speaker identifies himself via the relationship to that space. The creative portion is accompanied by a critical introduction that looks at the intersections of poetry and the lyric essay.
Date: May 2019
Creator: Carter, Justin
System: The UNT Digital Library
Building a Collaborative Smartphone Application for Blind and Low Vision Visitors at the Dallas Museum of Art (open access)

Building a Collaborative Smartphone Application for Blind and Low Vision Visitors at the Dallas Museum of Art

The goal of my study is to develop a mobile application to enable all visitors, including blind and low-vision visitors, to autonomously gather and share information about interpretations of art and to have a fully independent museum-going experience. With an application, blind visitors have more access to opportunities and tools in the museum, which empowers their museum experience. My study used a qualitative, mixed-methods approach to research how blind and low vision museum visitors might increase their independence in the museum space and discover ways to equalize their access without relying on museum educators. In carrying out my study, I conducted interviews and collected data based on observations and transcribed and analyzed them using a grounded theory approach. I used Freire's theory of pedagogy of the oppressed and hooks' theory of education as the practice of freedom to frame my study.
Date: May 2019
Creator: Aljuidan, Hanan Abdulaziz M
System: The UNT Digital Library
The Civilian Conservation Corps in Big Bend National Park (open access)

The Civilian Conservation Corps in Big Bend National Park

During the New Deal, the Civilian Conservation Corps (CCC) put young men to work in state and national parks across the United States. One of such parks, Big Bend National Park, is the focus of this study. The CCC had two camps within the park, one from 1934 to 1937 and another from 1940 to 1942. During their time in Big Bend, the CCC constructed many projects including a road, trails, cabins, and other various structures. The purpose of this study is to delineate the role of the CCC in creating Big Bend National Park and the experience of the CCC during their time in the Big Bend camp. This study determines the role of the CCC through a discussion of the planning done by the CCC for Big Bend National Park and the work completed by the CCC in the park. In doing so, it argues that the CCC played a substantial and significant role in the development and character of the park. This study works to understand the experience of the CCC in Big Bend through a discussion of education, safety, and an investigation of a commanding officer. Through this discussion, the role of the federal government and …
Date: May 2019
Creator: Jackson, Kimberly
System: The UNT Digital Library

Cold-Formed Steel Member Connections Using BAC Screw Fasteners

Access: Use of this item is restricted to the UNT Community
In this project, the main research objective is intend to seek criteria for evaluating the capacity of BAC screw fasteners with mixed configuration of waterproof seal washer, sealer tape and different pre-drill holes to determine shear and tension strength values for the screws used in cold-formed steel connections. The thesis presents the design methods and test program conducted to investigate the behavior and strength of the screw connections in shear and tension test. Test results were compared with AISI design provisions to determine if new design equations will be developed for those screws used in BAC cooling tower applications. LRFD resistance factors and ASD safety factors were investigated to the proposed design equations.
Date: May 2019
Creator: Li, Xun
System: The UNT Digital Library
College and Career Readiness of Students with Autism (open access)

College and Career Readiness of Students with Autism

With one in every 59 individuals now diagnosed with autism spectrum disorder (ASD), there is a significant increase in college enrollment for these students, yet, alarmingly, this population has the highest college dropout rate. Using Rawl's social justice theory as the frame, this qualitative study identified the perceptions of students with ASD, their college professors, and the director of the Office of Disability Accommodation (ODA). Perceptions were examined through open-ended surveys regarding awareness of autism, knowledge of student civil rights, and the availability and adequacy of resources provided through the ODA. In addition, the students with autism participated in semi-structured face-to-face interviews. The findings of this study are consistent with other studies in reflecting barriers experienced by students with ASD, such as poor transition planning, communication, and self-advocacy limitations. The variance among reported perceptions revealed a lack of awareness and continuity of resources and support for students with autism, hindering their successful transition from high school to and through post-secondary education. Both students and professors expressed a lack of knowledge of students' rights at the college level and of how to access needed accommodations. These findings reveal the need for a greater awareness of supports needed by students with ASD …
Date: May 2019
Creator: Stello, Christina N
System: The UNT Digital Library
Comparison and Genetic Analysis of Host Specificity in Cluster BD1 Bacteriophages infecting Streptomyces (open access)

Comparison and Genetic Analysis of Host Specificity in Cluster BD1 Bacteriophages infecting Streptomyces

Bacteriophages are viruses that specifically infect bacteria. When a phage infects a bacterium, it attaches itself to the surface of the bacteria and injects its DNA into the intracellular space. The phage DNA hijacks the cellular machinery of the bacteria and forces it to produce phage proteins. Eventually, the bacteria cell bursts or lyses, releasing new phage. The bacteria act as a host for phage reproduction. The ability for a phage to infect multiple bacterial species is known as host range. In siphoviridae bacteriophages, host range is thought to primarily be determined by proteins at the tip of their tail fibers. These proteins act as anti-receptors to specific receptors on the surface of bacteria. In siphoviridae Gram-positive infecting phages, the genes that code these proteins are typically located between the tape measure protein gene and the endolysin gene. It is hypothesized that phages that have similar anti-receptor proteins will have similar host range. In this study, the host ranges of 12 BD1 bacteriophages were tested on 9 different Streptomyces species. In these 12 phages, the genes between the tape measure protein gene and endolysin gene were compared. The 12 phages had high levels of variability in these genes. Five genes …
Date: May 2019
Creator: Klug, Hannah
System: The UNT Digital Library

Complex-Restricted Repetitive Patterns of Vocal Behavior of Individuals with High Functioning Autism: An Innovative Intervention

Access: Use of this item is restricted to the UNT Community
Repetitive verbal patterns of speech are a trait associated with high-functioning autism (HFA). For some, this higher-order restricted, repetitive behavior impedes learning, social opportunities, and access to work environments. Despite emerging motivation for establishing social relationships, some individuals with HFA lack the behavioral prerequisites to establish meaningful relationships. The purpose of this study is to demonstrate the effectiveness of teaching interaction to decrease higher-order verbal restricted and repetitive behaviors (RRBs) for four adults with HFA. Through a multiple baseline design across participants, individuals were exposed to a function-based intervention (i.e., teaching interaction) that systematically taught and reinforced alternative communicative behaviors while interrupting repetitive speech with specific feedback. Teaching interaction effectively reduced RRBs and increased alternative conversation for all four participants. Three of the four participants elected to participate in post-intervention maintenance sessions that occurred in individualized naturalistic settings. Their conversation behaviors maintained with one participant receiving one booster session.
Date: May 2019
Creator: Flatt, Kimberlee Kay
System: The UNT Digital Library
Computational and Experimental Studies of the Photoluminescence, Reactivity and Structural Properties of d10 and d8 Metal Complexes (open access)

Computational and Experimental Studies of the Photoluminescence, Reactivity and Structural Properties of d10 and d8 Metal Complexes

Computational chemistry has gained interest as a characterization tool to predict photoluminescence, reactivity and structural properties of organic and transition metal complexes. With the rise of methods including relativity, these studies have been expanded to the accurate modeling of luminescence spectra of complexes with considerable spin-orbit splitting due to heavy metal centers as well as the reaction pathways for these complexes to produce natural products such as hydrogen gas. These advances have led to the synthesis and utility of more effective catalysis as well as the development of more effective organic light emitting diodes (OLEDs) through the incorporation of organometallic complexes as emitters instead of typical organic emitters. In terms of significant scientific advancement presented in this work is in relation to the discovery of significant spin-orbit splitting in a gold(I) alkylphosphine complex, where the splitting results in the states that emit in different colors of the visible region of the electromagnetic spectrum. This work also reveals the discovery both computationally and experimentally, of a genuine polar-covalent bond between two-closed shell metals. This work highlights a complex with an incredibly short gold(I) – copper(I) intermetallic distance leading to a vibrational frequency and dissociation energy that is on par with those …
Date: May 2019
Creator: Otten, Brooke Michelle
System: The UNT Digital Library