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Nitrogen Vacancy Centers as Quantum Sensors

There has been a growing interest in nitrogen-vacancy (NV) centers as high precision sensors in biology, chemistry, and physics. NV centers are naturally occurring defects in diamonds. They can detect nanoscale perturbations in local temperature, pressure, magnetic and electric fields. These quantum sensors perform optimally in ambient conditions, and their biocompatibility permits their use in vivo. The electronic states of the NV center can be…


Low Temperature Combustion of C5 Cyclic Molecules

Probing reaction mechanisms during low-temperature combustion of cyclopentane, which is a representative naphthene species, is necessary for building a broader understanding of the effect of functional groups present in C5 cyclic biofuels, such as cyclopentanol and cyclopentanone. At temperatures below 1000 K, competing reactions of naphthenes include ring-opening of initial radicals (Ṙ) and oxidation of Ṙ via reaction with O2 that yields…


Semiconductor Quantum Dots: Theory, Production, and Application

Semiconductor quantum dots are quantum confined systems that exist on the nanometer scale. A close examination into the properties of these zero-dimensional dots offers insight into their highly tunable chemistry and optics. This high tunability, in turn, promotes their use in a wide variety of interdisciplinary fields such as photovoltaics and bioimaging. Since the discovery of quantum dots, around 40 years ago, they have been the spark of much…


Construction of a Cavity-Enhanced Transient Absorption Spectrometer for Ultrafast Molecular Beam Measurements

Ultrafast spectroscopy is a powerful tool in order to probe transient dynamics of a variety of chemically relevant systems. Traditional ultrafast spectroscopy is done in either a thin film or solution phase as the concentration of the samples can easily yield high signals at relatively low powers, however these measurements are subject to solvation effects and can have a difficult time agreeing with theoretical models and other experimental…


Comparison of Multifidelity Machine Learning Models for Potential Energy Surfaces

Multifidelity modeling is a technique for fusing the information from two or more datasets into one model. It is particularly advantageous when one dataset contains few accurate results and the other contains many less accurate results. Within the context of modeling potential energy surfaces, the low fidelity dataset can be made up of a large number of inexpensive energy computations that provide adequate coverage of the N-dimensional space…


Vibrational Spectral Signatures and Ultrafast Dynamics of Strong H-bonds Investigated with Cryogenic Ion and 2D IR Spectroscopies

H-bonding interactions and proton transfer processes play central roles throughout chemistry and biology. Spectroscopic studies that directly probe strong H-bonds and proton transfer reactions, however, remain a formidable experimental challenge. We aim to characterize vibrational spectral signatures and dynamics of strong H-bonds by complementing high-resolution gas-phase techniques (cryogenic ion spectroscopy) with ultrafast time-resolved…


Gas-Phase Copper Clusters: Model for the CO2 Reduction Catalyst?


Seeking the Tricorder: Evolution of the NASA Anomaly Gas Analyzer

Dr. Jeffrey S. Pilgrim, winner of the 2023 UGA Chemistry Distinguished Alumnus Award, is President and founder of Vista Photonics, an optical instrumentation company located in Las Cruces, NM. He formed the corporation in June 2003 to develop and commercialize optical gas sensing technologies and instrumentation. Before starting Vista Photonics, Dr. Pilgrim worked as a Senior Research Scientist in a similar research and development environment…


Alginate Gels Structure-Thermodynamic Relationship with Water and Counterions

Microbial communities are predominantly found in biofilms, which are composed of extracellular polymeric substances (EPS). The EPS matrix is engineered and reconfigured by microbes, making it difficult to distinguish between the biotic and abiotic origins of biofilm properties. To establish this distinction, simplify models of the EPS matrix, the study uses molecular dynamic(MD) simulation to predict the nanoscale structure of a model…


Field-Free Molecular Alignment and Orientation

Control of molecular orientation and alignment has been a longstanding goal in chemical reaction dynamics because the outcome of chemical reactions inherently depends on the relative orientation of the colliding species. The earliest methods for obtaining molecular alignment and orientation relied on static electric fields strong enough to overcome the molecule's rotational energy, but these types of techniques are limited by the relatively low…
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