Phys Chem/Chem Phys Seminar

More than physics, more than data: Integrated machine-learning models for chemistry

When
-

Abstract: Machine-learning techniques are often applied to perform "end-to-end" predictions, that is to make a black-box estimate of a property of interest using only a coarse description of the corresponding inputs.
In contrast, atomic-scale modeling of matter is most useful when it allows to gather a mechanistic insight into the microscopic processes that underlie the behavior of molecules and materials. 

Nanomaterials Enable Delivery of Genetic Material Without Transgene Integration in Mature Plants

When
-

Abstract: Genetic engineering of plants is at the core of sustainability efforts, natural product synthesis, and agricultural crop engineering. The plant cell wall is a barrier that limits the ease and throughput with which exogenous biomolecules can be delivered to plants. Current delivery methods either suffer from host range limitations, low transformation efficiencies, tissue regenerability, tissue damage, or unavoidable DNA integration into the host genome.

Cold chemistry in hot cores: exploring the early origins of chemical complexity in nascent stellar systems

When
-

Abstract: The interstellar medium provides an enormous laboratory for the exploration of chemistry of various kinds. But it is not a laboratory that we control, and its results - while resting on processes that individually may occur very rapidly - unfold on timescales that are typically much longer than a human lifetime. Our observations of the molecular compositions of interstellar clouds and star-forming regions represent only snapshots of a process of chemical evolution that must be pieced together through various means.

Rapid Diagnostics for Infectious Diseases Using Gold Nanoparticles

When
-

Abstract: The global COVID-19 pandemic has underscored the need for innovations in disease diagnostics.  Paper immunoassays, such as lateral flow assays, have been a critical tool for infectious diseases. These assays are low-cost, can be used in rugged environments, and possess sample-to-answer times of minutes, so they are attractive for widespread deployment for disease surveillance, quarantining, and treatment.  Biological fluids such as blood or saliva is added to the paper strip, which wicks through.

Quantum-State Control on Multidimensional Potential Energy Surfaces: Driving Chemical Outcomes with Spectroscopic Accuracy

When
-

Abstract: In bimolecular collisions of atmospherically-relevant molecules such as open-shell radicals and alkanes, relative molecular configurations can significantly change reactive and non-reactive outcomes. To probe this isomer-dependence, experiments are needed that can quantify both the initial molecular configuration and internal energy of the collision partners with spectroscopic accuracy.

When Noise is the Signal: Highlights in Qubit-Based Quantum Spectral Estimation

When
-

Abstract: Accurate characterization and control of open quantum systems exposed to realistic, spatio-temporally correlated noise are vital for exploiting the full potential of quantum technologies. Thanks to their exquisite sensitivity to the surrounding environment, qubits can be naturally considered as “spectrometers”, or sensors, of their own noise.

Forces on Everything Everywhere All at Once

When
-

Abstract: In order to perform some of their most important functions, cells must be able to generate, sense, and respond to mechanical forces. Many mechanosensing proteins have been discovered that are believed to change their behavior in a predictable and repeatable way when they are under mechanical tension. Yet, in most of these cases, we don't know the molecular details of how this force shifts the conformations adopted by the protein, or how this then leads to a concomitant change in function.

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

When
-

Abstract: 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 solution-phase experiments (transient absorption, 2D IR).