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Utah State University

2023

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Full-Text Articles in Physical Sciences and Mathematics

Search For Osme Bonds With Π Systems As Electron Donors, Xin Wang, Qingzhong Li, Steve Scheiner Dec 2023

Search For Osme Bonds With Π Systems As Electron Donors, Xin Wang, Qingzhong Li, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The Osme bond is defined as pairing a Group 8 metal atom as an electron acceptor in a noncovalent interaction with a nucleophile. DFT calculations with the ωB97XD functional consider MO4 (M = Ru, Os) as the Lewis acid, paired with a series of π electron donors C2H2 , C2H4 , C6H6 , C4H5N, C4H4O, and C4H4S. The calculations establish interaction energies in the range between 9.5 and 26.4 kJ/mol. Os engages in stronger interactions than does Ru, …


Teaching Reproducibility To First Year College Students: Reflections From An Introductory Data Science Course, Brennan L. Bean Dec 2023

Teaching Reproducibility To First Year College Students: Reflections From An Introductory Data Science Course, Brennan L. Bean

Journal on Empowering Teaching Excellence

Access the online Pressbooks version of this article here.

Modern technology threatens traditional modes of classroom assessment by providing students with automated ways to write essays and take exams. At the same time, modern technology continues to expand the accessibility of computational tools that promise to increase the potential scope and quality of class projects. This paper presents a case study where students are asked to complete a “reproducible” final project in an introductory data science course using the R programming language. A reproducible project is one where an instructor can easily regenerate the results and conclusions from the submitted …


Water Main Break Rates In The Usa And Canada: A Comprehensive Study, Steven L. Barfuss Dec 2023

Water Main Break Rates In The Usa And Canada: A Comprehensive Study, Steven L. Barfuss

Reports

Deteriorating Infrastructure

Municipalities and the people they serve depend on pipe networks that provide safe drinking water. This piping is underground, out of sight, and often neglected.

Overall assessment of water infrastructure condition is not good. Using the US as an example:

  • In 2009, the American Society of Civil Engineers (ASCE) issued a US report card and gave a D- to drinking water infrastructure.
  • In 2017, the grade improved to a D.
  • In 2021, the grade was raised to a C-, better but still not good.
  • Utilities are currently losing 11% of their water to leakage.
  • Pipe life estimates of …


Tropical Atlantic Temperature And Hydrologic Shifts During The Paleocene-Eocene Thermal Maximum, Chels Howard Dec 2023

Tropical Atlantic Temperature And Hydrologic Shifts During The Paleocene-Eocene Thermal Maximum, Chels Howard

All Graduate Theses and Dissertations, Fall 2023 to Present

The Paleocene-Eocene Thermal Maximum (PETM) is a geologic climate event that is studied heavily due to the similarities to anthropogenic climate change. This event occurred approximately 56 million years ago (Ma) and is characterized by a rapid release of carbon into the atmosphere, which resulted in an increase in temperature and a change in global climate events such as changes in patterns of evaporation and precipitation. We see this effect occurring in modern anthropogenic climate change due to the burning of fossil fuels releasing carbon dioxide (CO2) into the atmosphere. In this study I use elemental data of …


Movement Patterns Of A Federally Endangered Minnow In A Fragmented Desert River, Martinique J. Chavez Dec 2023

Movement Patterns Of A Federally Endangered Minnow In A Fragmented Desert River, Martinique J. Chavez

All Graduate Theses and Dissertations, Fall 2023 to Present

Fishes are unified in their need to move within the systems they occupy, and their movement patterns can be fundamental to their ecology and survival. Many large rivers in North America are fragmented by dams that modify natural flow regimes, compromise connectivity, and imperil freshwater fishes dependent on unrestricted movement in order to complete their life history. Coincident with widespread river fragmentation, are the declines of numerous endemic desert fishes in the American southwest. The Rio Grande Silvery Minnow (Hybognathus amarus, RGSM), has experienced a 95% reduction in its historical range and is now restricted to a highly …


Solar Flare Prediction From Extremely Imbalanced Multivariate Time Series Data Using Minimally Random Convolutional Kernel Transform, Kartik Saini Dec 2023

Solar Flare Prediction From Extremely Imbalanced Multivariate Time Series Data Using Minimally Random Convolutional Kernel Transform, Kartik Saini

All Graduate Theses and Dissertations, Fall 2023 to Present

Solar flares are characterized by sudden bursts of electromagnetic radiation from the Sun's surface, and caused by the changes in magnetic field states in solar active regions. Earth and its surrounding space environment can suffer from various negative impacts caused by solar flares ranging from electronic communication disruption to radiation exposure-based health risks to the astronauts. In this paper, we address the solar flare prediction problem from magnetic field parameter-based multivariate time series (MVTS) data using multiple state-of-the-art machine learning classifiers that include MINImally RandOm Convolutional KErnel Transform (MINIROCKET), Support Vector Machine (SVM), Canonical Interval Forest (CIF), Multiple Representations SEQuence …


Prospects And Constraints For A Recreational Fishery On East Canyon Creek At The 910 Ranch, S. Bishop, A. Garner, G. Mclaughlin, T. Oman, N. Omer, C. Stewart Dec 2023

Prospects And Constraints For A Recreational Fishery On East Canyon Creek At The 910 Ranch, S. Bishop, A. Garner, G. Mclaughlin, T. Oman, N. Omer, C. Stewart

Watershed Sciences Student Research

Summit County Lands and Natural Resources has retained students from Utah State University’s Management and Restoration of Aquatic Ecosystems program to evaluate current conditions of East Canyon Creek (ECC) in the 910 Ranch and propose prospects, constraints, and potential actions to establish a recreational trout fishery.


Deep Learning With Effective Hierarchical Attention Mechanisms In Perception Of Autonomous Vehicles, Qiuxiao Chen Dec 2023

Deep Learning With Effective Hierarchical Attention Mechanisms In Perception Of Autonomous Vehicles, Qiuxiao Chen

All Graduate Theses and Dissertations, Fall 2023 to Present

Autonomous vehicles need to gather and understand information from their surroundings to drive safely. Just like how we look around and understand what's happening on the road, these vehicles need to see and make sense of dynamic objects like other cars, pedestrians, and cyclists, and static objects like crosswalks, road barriers, and stop lines.

In this dissertation, we aim to figure out better ways for computers to understand their surroundings in the 3D object detection task and map segmentation task. The 3D object detection task automatically spots objects in 3D (like cars or cyclists) and the map segmentation task automatically …


Advanced Caching And Streaming For Large Scale Point Cloud Data Visualization On The Web, Pravin Poudel Dec 2023

Advanced Caching And Streaming For Large Scale Point Cloud Data Visualization On The Web, Pravin Poudel

All Graduate Theses and Dissertations, Fall 2023 to Present

Point clouds are widely used in various applications such as 3D modeling, geospatial analysis, robotics, and more. One of the key advantages of 3D point cloud data is that, unlike other data formats like texture, it is independent of viewing angle, surface type, and parameterization. Since each point in the point cloud is independent of the other, it makes it the most suitable source of data for tasks like object recognition, scene segmentation, and reconstruction. Point clouds are complex and verbose due to the numerous attributes they contain, many of which may not be always necessary for rendering, making retrieving …


Phosphorus Dynamics In Calcareous Soils Amended With Organic Matter, Logan Banner Dec 2023

Phosphorus Dynamics In Calcareous Soils Amended With Organic Matter, Logan Banner

All Graduate Reports and Creative Projects, Fall 2023 to Present

Phosphorus (P) is considered immobile in calcareous soils. Organic matter is known to enhance P mobility in these soils. Few studies have considered what role iron oxides might play in P sorption in calcareous soils, especially in the presence of soluble organic matter. This study investigated P sorption dynamics in sand-based, simulated soil systems in the absence or presence of 5 mM carbon (C) as humic acid (HA). Treatments included combinations of dicalcium phosphate dihydrate (DCPD), calcite, and ferrihydrite. Solutions containing 10 mg P L-1 in a background of 0.01 M CaCl2were equilibrated with each solid treatment …


Analyzing The Impacts Of Beaver Dam And Beaver Dam Analog Complexes To Stream Ecology Within The Intermountain West, J. Marshall Wolf Dec 2023

Analyzing The Impacts Of Beaver Dam And Beaver Dam Analog Complexes To Stream Ecology Within The Intermountain West, J. Marshall Wolf

All Graduate Theses and Dissertations, Fall 2023 to Present

Streams, rivers, and their floodplains throughout the world are impaired due to human modifications. Recent research has demonstrated that restoration projects prioritizing the proper functioning of ecosystems have better restoration outcomes than projects which focus on restoring form alone. Throughout North America, beaver-mediated restoration is becoming a leading method for improving the functioning of stream ecosystems that are in a degraded state. In areas where beaver are absent or the habitat is too degraded to currently permit their dam building, man-made beaver dam analogs (BDAs) are being used to restore stream habitat with an eye to future beaver recolonization. However, …


An Ensemble Approach For Mapping Snow Water Equivalent In Utah, Logan Schneider Dec 2023

An Ensemble Approach For Mapping Snow Water Equivalent In Utah, Logan Schneider

All Graduate Theses and Dissertations, Fall 2023 to Present

Mountain snowpack is an important resource for water management planning in Utah. Snow water equivalent (SWE) is the amount of water contained in a snowpack. A few organizations predict SWE throughout the United States but struggle making accurate predictions in mountainous regions. Weather stations provide accurate measurements of SWE but have limited spatial coverage that hinders the ability to make accurate estimates statewide. This thesis examines the accuracy of current models and proposes using local weather measurements to improve upon national level predictions. An R statistical software package named rsnodas implements this process while allowing the public access to a …


Inundated Vegetation Response To Ongoing Restoration And Its Impacts On Fish Community Structure, Emmanuel J. May Dec 2023

Inundated Vegetation Response To Ongoing Restoration And Its Impacts On Fish Community Structure, Emmanuel J. May

All Graduate Theses and Dissertations, Fall 2023 to Present

Shallow lake ecosystems and their associated wetland habitats globally are subject to non-native species introductions, nutrient loading, and water level fluctuations, each of which can decrease vegetated habitat availability, exposing vulnerable native aquatic species to predation. Managers are frequently tasked with mitigating native species declines by restoring vegetation considered crucial for their survival. However, restoring vegetation can be challenging in the presence of multiple stressors, requiring managers to assess the relative importance of the different stressors limiting vegetation recovery.

Utah Lake is a large shallow lake subject to multiple stressors and has shifted from a mesotrophic lake with abundant aquatic …


Collaborative Task Completion For Simulated Hexapod Robots Using Reinforcement Learning, Tayler Don Baker Dec 2023

Collaborative Task Completion For Simulated Hexapod Robots Using Reinforcement Learning, Tayler Don Baker

All Graduate Theses and Dissertations, Fall 2023 to Present

There is growing interest in developing autonomous systems capable of exhibiting collaborative behaviors. Using methods such as reinforcement learning is another way to train multiple robots for collaborative task completion. This study was able to successfully in simulation train multiple hexapod robots to push a target to a designated goal collaboratively. This required each robot to learn how find the target and push that target to a goal. This work suggests that using reinforcement learning for collaborative task completion for hexapod robots may simplify the complexity of the software and improve the decisions that they make.


Computational Study About Noncovalent Bonding Systems Involving Halogen, Chalcogen And Pnicogen Bonds, Jia Lu Dec 2023

Computational Study About Noncovalent Bonding Systems Involving Halogen, Chalcogen And Pnicogen Bonds, Jia Lu

All Graduate Theses and Dissertations, Fall 2023 to Present

First terms used in this thesis are introduced and defined as follows. In the periodic table, the elements in the 17th column are named halogen including fluorine (F), chlorine (Cl), bromine (Br) and iodine (I). The elements in the 16th column are named chalcogen including oxygen (O), sulfur (S), selenium (Se) and tellurium (Te). The elements in the 15th column are named pnicogen including nitrogen (N), phosphorus (P), arsenic (As) and antimony (Sb).

After hydrogen bonds (B-H⋅⋅⋅B) are well studied and understood by scientists and researchers, halogen bonds (R-X⋅⋅⋅B) have drawn attention due to the similarities in …


Controls On Sediment Connectivity In Fluvial Networks Impacted By Wildfire Across Utah, Alec Arditti Dec 2023

Controls On Sediment Connectivity In Fluvial Networks Impacted By Wildfire Across Utah, Alec Arditti

All Graduate Theses and Dissertations, Fall 2023 to Present

Flooding and sedimentation caused by wildfire are among the greatest threats to watersheds, fish populations and reservoirs in the western US. Burned landscapes are at risk for increased runoff and erosion and have the potential to transport sediment that may put downstream resources at risk. The ability of the channel to transport sediment downstream, known as the connectivity, is important for determining where impacts may occur. Sediment bottlenecks are locations within the watershed where local conditions produce a persistent decrease in downstream connectivity of sediment, resulting in increased sediment deposition and potentially a substantial modification of the local channel and …


Multi-Objective Water Management In Idaho's Henrys Fork Watershed: Leveraging Reservoir Operation And Groundwater Pathways To Benefit Aquatic Habitat, Christina N. Morrisett Dec 2023

Multi-Objective Water Management In Idaho's Henrys Fork Watershed: Leveraging Reservoir Operation And Groundwater Pathways To Benefit Aquatic Habitat, Christina N. Morrisett

All Graduate Theses and Dissertations, Fall 2023 to Present

Multi-user water management is a challenging arena further complicated by climate change. This research is based in the Henrys Fork, Snake River, Idaho—an agricultural watershed that exemplifies those throughout the semi-arid American West. This dissertation uses an integrated approach that considers groundwater-river relationships, farm-scale decisions and basin-scale outcomes, upstream reservoir operation for downstream aquatic habitat, water rights, and collaborative stakeholder management to identify drought adaptation strategies accordingly.

Chapter 2 uses an interdisciplinary approach to quantify how improvements to irrigation efficiency at the farm-scale (i.e., converting from flood to sprinkler irrigation) can add up to affect hydrology at the landscape-scale and …


Optimal Stopping Of Multi-Robot Exploration For Unknown, Bounded Environments, Trey D. Crowther Dec 2023

Optimal Stopping Of Multi-Robot Exploration For Unknown, Bounded Environments, Trey D. Crowther

All Graduate Theses and Dissertations, Fall 2023 to Present

Limited resources and uncertainty pose a substantial problem for multi-robot exploration of unknown environments. This research paper looks to determine the optimal time to terminate robot exploration while maximizing information gathered. Whilst making this determination, the system's resources and capabilities must be taken into account. To see if our strategy works, we ran many simulations in varying environments. The results of this research are important for real-world uses like robot exploration, search and rescue missions, and automated surveillance. Determining when to stop exploring can help the system save resources, explore faster, and make better decisions.


Analysis Of Student Behavior And Score Prediction In Assistments Online Learning, Aswani Yaramala Dec 2023

Analysis Of Student Behavior And Score Prediction In Assistments Online Learning, Aswani Yaramala

All Graduate Theses and Dissertations, Fall 2023 to Present

Understanding and analyzing student behavior is paramount in enhancing online learning, and this thesis delves into the subject by presenting an in-depth analysis of student behavior and score prediction in the ASSISTments online learning platform. We used data from the EDM Cup 2023 Kaggle Competition to answer four key questions. First, we explored how students seeking hints and explanations affect their performance in assignments, shedding light on the role of guidance in learning. Second, we looked at the connection between students mastering specific skills and their performance in related assignments, giving insights into the effectiveness of curriculum alignment. Third, we …


Reducing Inputs And Adding Value To Turfgrass Systems Through Clover Inclusion And Plant Growth-Promoting Rhizobacteria Applications, Paige E. Boyle Dec 2023

Reducing Inputs And Adding Value To Turfgrass Systems Through Clover Inclusion And Plant Growth-Promoting Rhizobacteria Applications, Paige E. Boyle

All Graduate Theses and Dissertations, Fall 2023 to Present

Recently, the US has seen an expansion in the amount of turfgrass land cover (lawns, parks, roadsides, sports fields, and golf courses), as well as an interest in reducing fertilizer, water, and pesticide use in these grass systems. To help maintain quality and function while reducing resource inputs, two promising approaches have emerged: planting clover into lawns and applying plant growth-promoting rhizobacteria.

White clover and grass mixtures have been studied for their ability to cut down on fertilizer usage and provide a uniform, dark green lawn, but other clover types have not been as widely studied and may provide similar …


Using Gamification To Foster Student Resilience And Motivation To Learn, And Using Games To Teach Significance Testing Concepts In The Statistics Classroom, Todd Partridge Dec 2023

Using Gamification To Foster Student Resilience And Motivation To Learn, And Using Games To Teach Significance Testing Concepts In The Statistics Classroom, Todd Partridge

All Graduate Theses and Dissertations, Fall 2023 to Present

Two studies are outlined in this dissertation.

In the first study, elements of Super Mario Bros. videos games were used to change the way college students in a beginners’ statistics course were graded on their work. This was part of an effort to help students remain optimistic in the face of challenging coursework and even failure on assignments and tests. The study shows that the changes made to the grading structure did help students to keep trying and to use the materials given to them by their professor until they achieved their desired grade in the course, and suggests ways …


Constraining Silicate Weathering During The Middle Eocene Climatic Optimum (Meco) Using Radiolarian Ge/Si, Olivia R. Laub Dec 2023

Constraining Silicate Weathering During The Middle Eocene Climatic Optimum (Meco) Using Radiolarian Ge/Si, Olivia R. Laub

All Graduate Theses and Dissertations, Fall 2023 to Present

Silicate weathering has long been considered a fundamental component of the earth system and has been cited as one of, if not the primary stabilizing feedback for climate. However, recent work has shown that the role of silicate weathering in the climate system is more complicated and dynamic than previously assumed. In this study I examine the role of weathering in the enigmatic warming event, the Middle Eocene Climatic Optimum (MECO) that occurred approximately 40 Ma. This event works as a good case study as there are multiple features of the MECO that differentiate it from other warming events that …


Characterization Of The Long-Distance Dispersal Kernel Of White-Tailed Deer And Evaluating Its Impact On Chronic Wasting Disease Spread In Wisconsin, Mennatallah Gouda Dec 2023

Characterization Of The Long-Distance Dispersal Kernel Of White-Tailed Deer And Evaluating Its Impact On Chronic Wasting Disease Spread In Wisconsin, Mennatallah Gouda

All Graduate Theses and Dissertations, Fall 2023 to Present

Chronic Wasting Disease (CWD) is a fatal, untreatable neurodegenerative disease that infects deer and related species. It is highly contagious and caused by abnormal malfunction and assembly of normal cellular proteins into aggregation-prone proteins. The Centers for Disease Control and prevention report that the prevalence of CWD in free-ranging deer in the US is still relatively low. However, in several states the infection rates exceed 1 deer in 10. Deer may uptake CWD from direct interaction with infected individuals or from the environment. Infected individuals shed CWD into the environment through feces, urine, saliva or carcasses, and long-distance dispersal of …


Fire And Flow: Assessing The Long-Term Effects Of Wildfires And Impact Of High Flow Events On Phosphorus Concentrations In Mountain Streams, Rachel Watts Dec 2023

Fire And Flow: Assessing The Long-Term Effects Of Wildfires And Impact Of High Flow Events On Phosphorus Concentrations In Mountain Streams, Rachel Watts

All Graduate Theses and Dissertations, Fall 2023 to Present

Climate change has led to significant shifts in the Earth’s weather patterns, often leading to longer, more intense droughts, irregular but extreme storms, and more severe wildfires with longer burn durations. These weather pattern changes have frequently led to shifts in ecosystem dynamics, impacting aspects such as nutrient flux, species diversity, and overall habitat health. Regarding nutrient flux specifically, changes in phosphorus (P) concentrations can negatively impact stream systems as elevated levels can lead to toxic algal blooms, which can cause habitat degradation, loss of usable recreational areas, and large fish kills. A common trigger of these P spikes is …


Adversarially Reweighted Sequence Anomaly Detection With Limited Log Data, Kevin Vulcano Dec 2023

Adversarially Reweighted Sequence Anomaly Detection With Limited Log Data, Kevin Vulcano

All Graduate Theses and Dissertations, Fall 2023 to Present

In the realm of safeguarding digital systems, the ability to detect anomalies in log sequences is paramount, with applications spanning cybersecurity, network surveillance, and financial transaction monitoring. This thesis presents AdvSVDD, a sophisticated deep learning model designed for sequence anomaly detection. Built upon the foundation of Deep Support Vector Data Description (Deep SVDD), AdvSVDD stands out by incorporating Adversarial Reweighted Learning (ARL) to enhance its performance, particularly when confronted with limited training data. By leveraging the Deep SVDD technique to map normal log sequences into a hypersphere and harnessing the amplification effects of Adversarial Reweighted Learning, AdvSVDD demonstrates remarkable efficacy …


Designing And Studying Redox-Active Molecules For Energy Storage And Desalination, Wenda Wu Dec 2023

Designing And Studying Redox-Active Molecules For Energy Storage And Desalination, Wenda Wu

All Graduate Theses and Dissertations, Fall 2023 to Present

Since the fast growth of the global population, energy scarcity has become a new threat to modern society. Those commonly seen resources like fossil, coal, and natural gas are nonrenewable energies, which cannot be replenished by human-scale time. In contrast, wind, solar, and hydropower are the three main renewable green energies under development with great efforts around the world. However, the intermittent character of these powers raises a new question: how to store them properly on large scales? By 2021, more than 90% of the electricity storage was taken by Lithium-ion batteries (LIBs). The usage of lithium brings concerns about …


Ecology And Management Of Dyer's Woad (Isatis Tinctoria) In Northern Utah, Erin Marie Hettinger Dec 2023

Ecology And Management Of Dyer's Woad (Isatis Tinctoria) In Northern Utah, Erin Marie Hettinger

All Graduate Theses and Dissertations, Fall 2023 to Present

Dyer’s woad (Isatis tinctoria L.) is a non-native forb that continues to threaten natural areas throughout Northern Utah and much of the Intermountain West. Once introduced, dyer’s woad can become extremely invasive, decreasing forage quality, and displacing native species. While dyer’s woad is found throughout much of Northern Utah, its range in other states remains limited. If promptly managed, control success in these areas will be much higher and populations may be kept at bay before ecological damage becomes severe.

This project tested the ability of dyer’s woad seedlings to compete with common rangeland grasslands at varied densities as …


Climate Change-Driven Cumulative Mountain Pine Beetle-Caused Whitebark Pine Mortality In The Greater Yellowstone Ecosystem, William W. Macfarlane, Brian Howell, Jesse A. Logan, Ally L. Smith, Cashe C. Rasmussen, Robert E. Spangler Nov 2023

Climate Change-Driven Cumulative Mountain Pine Beetle-Caused Whitebark Pine Mortality In The Greater Yellowstone Ecosystem, William W. Macfarlane, Brian Howell, Jesse A. Logan, Ally L. Smith, Cashe C. Rasmussen, Robert E. Spangler

Watershed Sciences Faculty Publications

An aerial survey method called the Landscape Assessment System (LAS) was used to assess mountain pine beetle (Dendroctonus ponderosae)-caused mortality of whitebark pine (Pinus albicaulis) across the Greater Yellowstone Ecosystem (59,000 km2; GYE). This consisted of 11,942 km of flightlines, along which 4434 geo-tagged, oblique aerial photos were captured and processed. A mortality rating of none to severe (0–4.0 recent attack or 5.0–5.4 old attack) was assigned to each photo based on the amount of red (recent attack) and gray (old attack) trees visible. The method produced a photo inventory of 74 percent of …


Dynamics And Scaling Of Particle Streaks In High-Reynolds-Number Turbulent Boundary Layers, Tim Berk, Filippo Coletti Nov 2023

Dynamics And Scaling Of Particle Streaks In High-Reynolds-Number Turbulent Boundary Layers, Tim Berk, Filippo Coletti

Mechanical and Aerospace Engineering Faculty Publications

Inertial particles in wall-bounded turbulence are known to form streaks, but experimental evidence and predictive understanding of this phenomenon is lacking, especially in regimes relevant to atmospheric flows. We carry out wind tunnel measurements to investigate this process, characterizing the transport of microscopic particles suspended in turbulent boundary layers. The friction Reynolds number Re𝜏 = O(104) allows for significant scale separation and the emergence of large-scale motions, while the range of viscous Stokes number St+ = 18–870 is relevant to the transport of dust and fine sand in the atmospheric surface layer. We …


Relation Between Halogen Bond Strength And Ir And Nmr Spectroscopic Markers, Akhtam Amonov, Steve Scheiner Nov 2023

Relation Between Halogen Bond Strength And Ir And Nmr Spectroscopic Markers, Akhtam Amonov, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The relationship between the strength of a halogen bond (XB) and various IR and NMR spectroscopic quantities is assessed through DFT calculations. Three different Lewis acids place a Br or I atom on a phenyl ring; each is paired with a collection of N and O bases of varying electron donor power. The weakest of the XBs display a C–X bond contraction coupled with a blue shift in the associated frequency, whereas the reverse trends occur for the stronger bonds. The best correlations with the XB interaction energy are observed with the NMR shielding of the C atom directly bonded …