Synthesis opens the pathway to examine a plethora of complex structures. Whether the target is a naturally occurring compound or a proposed molecule never observed before, synthetic routes can be developed to help understand a variety of properties that the molecule can contain. Synthetic efforts have helped elucidate the absolute...
Recent advances in combinatorial chemistry, synthetic biology, and ‘omics’ research require high-throughput methods for performing and analyzing thousands to millions of reactions in one day. However, it is a challenge to engineer high-throughput systems that can autonomously conduct and analyze such a large number of reactions in a generalizable and...
While Li-ion batteries are currently the preferred energy storage technology, multivalent alternatives such as Mg should be considered. Magnesium metal has a high volumetric capacity and has been shown to cycle with no dendrite formation. However, the highly charged Mg2+ ion cannot easily diffuse into the oxide cathodes favored in...
The physical boundary layer, or interface, between two different phases of matter is the site of chemical and physical processes that are critical to many research fields. Many of these interfaces contain electric charge, which influences the structure and composition of the interfacial region and the interactions between the interface...
Polyolefins are the most versatile and widely used polymers worldwide. Depending on the polymer microstructure, polyolefins can exhibit a wide range of useful and tailored properties and applications. Metal-catalyzed coordinative olefin polymerization plays a center role in advancing polyolefin synthesis. This dissertation explores two strategies to modulate the polymer microstructures...
Spherical Nucleic Acids (SNAs) are unique class of nanomaterial characterized by a dense nucleic acid shell conjugated to a nanoparticle core. This radial orientation of oligonucleotides and architecture distinguishes SNAs from the components from which they are comprised. Specifically, unique chemical and biological properties emerge that are not observed with...
In this thesis, I present the development and benchmarking of several theoretical methods designed to enable the rigorous modeling of magnetic properties of molecules containing one or a few heavy atoms, particularly single-molecule magnets. The new methods use a full four-component treatment of relativity, allowing spin–orbit effects to be taken...
Oxide/aqueous and metal/metal oxide interfaces are essential for environmental remediation, catalysis, and corrosion inhibition, in addition to their potential implementation as energy transducers, consumer electronics, and coating products. While these interfaces are critically important, they are difficult to access experimentally under aqueous flow conditions. This thesis describes results obtained with...
When attached to another species (e.g. a nanoparticle), the sequence specificity of DNA can be repurposed to program interactions between such entities and to direct their formation into ordered structures. The research presented in this thesis aims to push the boundaries of structures that can be made via this approach....
Harnessing the metabolic potential of methanotrophic bacteria is a compelling strategy for the bioremediation of environmentally harmful methane gas. Methanotrophs can activate a 105 kcal/mol C-H bond in methane at ambient conditions using metalloenzymes called methane monooxygenases (MMOs). Particulate methane monooxygenase (pMMO) is a copper-dependent, membrane-bound enzyme that is the...
Molecules are highly social: they recognize one another and form bonds with those they are attracted to and repel those they are not. Some molecules establish strong bonds, while others form weak, transient associations. These interactions are ubiquitous in Nature and are integral to life. For at the basis of...
Label-free assays, and particularly those based on the combination of mass spectroscopy with surface chemistries, enable high-throughput experiments of a broad range of reactions. However, these methods can still require the incorporation of functional groups that allow immobilization of reactants and products to surfaces prior to analysis. In this thesis,...
Neurons are sensitive to the mechanical properties of their environment and show better growth, survival and differentiation when they are cultured in soft environments with mechanical properties similar to those of the brain compared to other tissues. Within the central nervous system (CNS), there is also a range of mechanical...
Organic solar cells (OSC) are a next generation solar energy technology that offers the advantages of scalable fabrication, light weight, flexibility, and earth-abundant starting materials. Despite tremendous advances in OSC power conversion efficiency (PCE) over the last decade, active layer material selection and optimization is still largely empirical. In order...
Self-Assembled Monolayers for MALDI-TOF Mass Spectrometry (SAMDI-MS) is a technique that combines self-assembling molecules of alkane disulfides on gold and MALDI-TOF mass spectrometry. By using well-defined monolayers with functionalizations that both prevent non-specific adsorption onto the surface and presents immobilization handles, it is possible to pull out analytes of interest,...
Natural gas is likely to become one of the main sources of carbon-based chemicals in the next century due to rapidly increasing natural gas production levels. This has created new incentives to find materials that are active and selective towards alkane partial oxidation reactions that are relevant for natural gas...
Thermoelectric modules that convert heat into electrical energy are attractive for improving global energy management. This thesis reports the synthesis and characterization of two new families of lead and tin chalcogenide alloys and focuses on the impact of the grain boundaries, phase segregation, and atomic vacancies on the electronic and...
The effective capture and detoxification of chemical warfare agents (CWAs) is a pressing need in the modern world. Materials are needed for both the destruction of weapon stockpiles and personal protection via fabric coatings or respirators. Attractive candidates for these applications include metal–organic frameworks (MOFs) – highly crystalline materials composed...
Raman spectroscopy is an analytical technique that utilizes inelastic scattering of light to obtain structural information of analyte molecules. The weak intrinsic process of Raman scattering, however, can be greatly enhanced when molecules are placed on or near a surface of noble metal with nanostructures. Discovered over 40 years, surface-enhanced...
The objective of molecular imaging is to noninvasively visualize biochemical events in a living system at the cellular level. Magnetic resonance imaging (MRI) is a promising modality for this goal due to its excellent resolution, unlimited depth penetration, and absence of harmful ionizing radiation. MRI techniques frequently use Gd(III)-based contrast...
This dissertation describes investigations into the two primary mechanisms by which the optical bandgap of colloidal quantum dots (QDs) may be post-synthetically modified: (i) by the quantum-confined Stark effect and (ii) by exciton-delocalizing surface capping ligands. This work demonstrates that through the use of ligand-exchange strategies that enable either of...
It is said across numerous disciplines, from biology to architecture to software engineering, that “form ever follows function.” This adage highlights the intimate relationship between structural characteristics and functional properties in many disparate fields of work. Here, we discuss how the catalytic activity and compressibility of metal–organic frameworks (MOFs) are...
Deciphering the targets of axonal projections plays a pivotal role in interpreting neuronal function and pathology. Neuronal tracers are indispensable neurobiology tools for elucidating advanced functions and interactions between different subregions of the brain. Commercially available neuronal tracers include small molecule dyes, viruses, and synthetic nanoparticles. Among these options, viral...
Total synthesis of natural products provides an avenue for investigation of complex chemical scaffolds, not only delivering access to biologically impactful molecules but also lending a deeper understanding of their inherent chemical reactivity. Expansion of reaction methodology, optimization of biological activity, and absolute structural confirmation can all be accomplished via...
Organic chromophores show great promise for energy and optoelectronic devices, due to their synthetic tunability and low production costs. In order to achieve this potential, their fundamental photophysical processes must be better understood. It has long been documented that chromophore packing at the molecular level has dramatic effect on electronic...
Cyclodextrin-based polymers (CDPs) are adsorbents based on supramolecular receptor chemistry and have emerged as a promising technology for organic micropollutant remediation. Micropollutants are small organic molecules which contaminate water systems from human related activities. The occurrence of micropollutants in water sources is associated with many negative health, economic, and ecological...
This dissertation describes the study of photoinduced charge transfer between QDs and molecular acceptors as a probe of the defects within ligand shells of QDs and as means to photocatalyze redox reactions. For charge transfer reactions to occur between QDs and molecules in bulk solution, the molecules must interact with...
A fundamental understanding of the photophysics involved in solar energy capture and conversion is crucial to the development of carbon-neutral energy technologies. Taking inspiration from nature, the photosynthetic reaction center (PSRC) is often modeled by simpler versions of its elements to allow for better control over the system and for...
Over the past 15 years, there have been significant developments in expanding the singlet fission (SF) library and understanding the SF mechanism. SF has been a topic of interest in recent years due to its potential applications in organic photovoltaics. During SF, a singlet exciton energetically down-converts into two triplet...
Part I: Design of Photo-Responsive Molecules towards Biomedical ApplicationsThe use of light to control systems provides numerous advantages such as spatiotemporal precision, non-invasive penetration, and precise energy input. Specifically, molecules that undergo photoinduced cleavage, photoremovable protecting groups (PPGs) have emerged as an active area of research due to their broad...
Formed through self-assembly of polynuclear node clusters and multitopic organic linkers, metal–organic frameworks (MOFs) are a class of three-dimensional crystalline materials. Due to their exceptional porosity, high surface areas, amenability to construction, chemical diversity, uniformly arrayed metal-containing nodes, and highly modular nature, MOFs are an ideal class of materials for...
The discovery of abundant reserves of shale gas over this past decade has reshaped the world’s energy landscape. It has renewed interests in the activation and conversion of methane as well as other light alkanes. While the oxidative coupling of methane (OCM) and oxidative dehydrogenation (ODH) of ethane and propane...
Chemical modifications of oligonucleotides (ONs) have advanced these molecules towards clinical approvals. On their own, native ONs have poor pharmacokinetic properties, such as rapid degradation by nucleases and poor cell uptake, which limit their potential therapeutic applications. Chemical modifications of ONs can increase their stability, alter their interactions with cells,...
The development of new catalytic methodologies for the precision synthesis of carbon-carbon bonds is central to the advancement of synthetic organic chemistry. Significant focuses of these efforts are made on the enantio- and diastereoselective synthesis of carbon frameworks, especially as chemists and biologists become more aware of the impact of...
Despite prevention and treatment, substantial risk for cardiovascular disease(CVD) remains in the population and CVD has been the leading global cause-of-death in past years.While high-density lipoprotein (HDL) markers such as HDL cholesterol (HDL-C) and HDL efflux (a cholesterol-transport-function assay) are associated with decreased risk of CVD, the mechanism of this...
Continuous and coordinated materials discovery efforts have amassed a wealth of knowledge concerning many general classes of materials. The number of known phases of all structure-types, however, is far less than number of possible materials dictated by the elements on the periodic table. Recently, with improved computational abilities and well-developed...
This dissertation seeks to explore how physical forces, notably through the use of magnetic nanoparticles and applied fields, can influence the structural outcomes of colloidal crystals engineered with DNA. Chapter 1 describes how both DNA and magnetic fields can direct the assembly of nanoparticles into periodic and sometimes crystalline materials....
The lanthanides, with their limited orbital effects and high oxophilicity, represent a class of catalytic metals highly distinguished from more commonly-utilized transition metals. Homogeneous lanthanide catalysts often afford high catalytic rates and impressive selectivity. However, challenges regarding the synthesis and utilization of highly air- and water-sensitive organo-lanthanide complexes have limited...
Electrochemical cell devices are increasingly being sought for energy conversion and storage applications due to their high efficiencies and their potential for operating free of greenhouse gas (GHG) emissions. Solid Acid Electrochemical Cells (SAECs), which most commonly employ CsH2PO4 (CDP) as the electrolyte component, are uniquely suited to meet the...
This dissertation investigates the use of organic and semiconductor nanomaterials as chromophores in solar fuels production and energy transfer-mediated [2+2] cycloadditions. A series of novel N-annulated perylene chromophore amphiphiles was synthesized via a modular synthesis. These perylene amphiphiles were found to self-assemble in aqueous solution, forming extended ribbon-like nanostructures that...
Discrete molecules, linear and branched polymers, and disordered cross-linked networks are well studied objects of chemical synthesis. However, two-dimensional polymers (2DPs) have been long missing from this continuum of molecular architectures, both in chemical synthesis and in Nature. Recently, new polymerization strategies and characterization methods have enabled the unambiguous realization...
Quantum dots (QDs) are promising photocatalysts due to their large extinction coefficient, large surface area-to-volume ratio, and stability upon irradiation. QDs have been studied in photocatalytic hydrogen production, CO2 reduction, and reduction of small organic molecules such as nitrobenzene. This dissertation describes the application of QDs in two photocatalytic cross-coupling...
Mixed-dimensional heterojunctions between two-dimensional (2D) materials and organic semiconductors is a rapidly growing field. This is motivated by the promise of leveraging the extraordinary properties of 2D materials with the synthetic tunability and reconfigurability of organic electronics, allowing the realization of new physics or devices that are not possible in...
In the first two decades of the 21st century, metal organic frameworks (MOFs) have attracted much attention in both fundamental-research and-industrial application areas. Derived from a vast library of both inorganic metal nodes and organic linker bridges, MOFs are crystalline materials whose structures and chemical environments can both be tuned...
Chirality and polarity describe orthogonal mechanisms of inversion symmetry breaking, which is the origin of valuable properties in crystalline materials including nonlinear optical activity, ferroelectricity, and piezoelectricity. Noncentrosymmetric (NCS) materials have numerous applications yet opportunities remain for cooperative coupling between chiral and polar basic building units to realize high-performance materials....
The opposing activities of phosphatases and kinases determine the phosphorylation status of proteins, yet kinases have received disproportionate attention in studies of cellular processes, with the roles of phosphatases remaining less understood. This dissertation describes the use of self-assembled monolayer laser desorption/ionization mass spectrometry (SAMDI-MS) together with peptide arrays to...
Two-dimensional (2D) covalent organic frameworks (COFs) are a class of crystalline polymer networks that polymerize and crystallize into layered structures, characterized by their atomically precise structure, permanent porosity and high modularity. Imine-linked COFs are one of the most important and promising classes of macromolecular sheets, which form by the condensation...
Molecular-oriented single-site heterogeneous catalysis is a powerful approach to address the long-lasting challenge of the structure-activity relationship in catalysis, as it allows molecular level control of the catalytic centers and thus the elucidation of reaction mechanisms. In this dissertation, single-site molybdenum-dioxo species have been immobilized on carbon supports, i.e. activated...
The idea that structure determines the properties of a material is a powerful concept in chemistry and in all fields in which chemistry is important, including engineering, medicine, and materials science. My research aims to better understand the structure-property relationships of a class of materials known as metal–organic frameworks (MOFs)....
Two-dimensional (2D) covalent organic frameworks (COFs) are a class of crystalline polymer networks that polymerize and crystallize into layered structures, characterized by their atomically precise structure, permanent porosity and high modularity. Imine-linked COFs are one of the most important and promising classes of macromolecular sheets, which form by the condensation...