INVENTING TECHNIQUES TO MEASURE AND UNDERSTAND CHEMICAL PROCESSES DOWN TO FEMTOSECOND TIME RESOLUTIONS, SINGLE-MOLECULE LENGTHS, AND PICOMOLAR CONCENTRATIONS
Chemistry as a physical science is unique in both interrogating and creating molecular structures. It illuminates and controls molecular systems through the design and development of tools to study atomic and molecular behavior. Through its focus on the energetics of chemical structure and transformation, it also provides the molecular foundation for all energy conversion technologies and the economic and societal benefits they provide. Leveraging a rich community of institutes, centers and training programs such as the Global Climate and Energy Project and Precourt Institute for Energy, Stanford scientists are developing new strategies to understand and manipulate atomic and molecular behavior, the interaction of light with matter, and the dynamics and energetics of bond rearrangements that are critical to new energy technologies.
Exploring the properties of matter at size scales ranging from single molecules to macroscopic materials, and at time scales from picoseconds to hours, requires new experimental and theoretical approaches and sophisticated electronic devices. Our scientists are driving these advances with emerging tools and technologies that can quantify measurements of atomic and molecular behavior with extraordinary sensitivity and precision.
Stanford pioneers in the use of synchrotron x-ray radiation use the next-generation light source, the free electron laser, to study chemical reactivity with stop-action timing. Using ultrafast optical methods, Stanford scientists capture the molecular motions of catalytic reactions over an unprecedented range of time scales, from tens of femtoseconds to ten microseconds. Other faculty have devised tools and techniques to examine molecules in extremely tiny volumes, characteristic of volumes inside cells and subcellular compartments. Pioneering work in the laser spectroscopy and microscopy of single molecules probes biological processes one molecule at a time, leveraging the development of super-resolved fluorescence microscopy surpassing the optical diffraction limit recognized in the 2014 Nobel Prize in Chemistry, and informing ongoing development of 2D and 3D super-resolution imaging.
Stanford photobiophysical studies examine light-driven long-distance electron transfer in photosynthetic reaction centers, one of the fastest known chemical reactions, and probes alternate pathways of electron transfer. Parallel studies develop molecular systems, analytical tools and theoretical approaches to understand electron transfer between electrodes and among redox species, with applications in sustainable battery technology and fuel chemistry.
Molecular Dynamics and Physical Properties
The use of lasers to study chemical reactions at the molecular level, pioneered at Stanford, led to seminal contributions to our understanding of molecular collision processes. New methods that predict and explain how atoms move in molecules are used both to design new molecules and to understand the behavior of those that already exist, including molecular responses to light and external force. High-quality [SW1] nanotubes from a Stanford-developed synthesis are widely used to investigate the electrical, mechanical, optical, electro-mechanical and thermal properties of quasi-one-dimensional systems.
Structure and Reactivity
Spectroscopy and theory combine to probe the electronic and geometric structures of transition metal sites, and their relationship to reactivity and function. Groundbreaking work from the first lab to clone myoglobin has demonstrated electrostatic contributions to enzyme activity, opening a new perspective on catalysis.
Studies integrating chemistry, biology, and physics investigate the assembly and function of macromolecular complexes and whole-cell factories, with particular focus on bacterial cell walls and biofilms – major targets of antibiotics and anti-infectives. New insights into enzymology are guiding studies of antibiotics biosynthesis in bacteria, and the role of the enzyme transglutaminase 2 in celiac disease Novel optical methods and applications of nanopillars as electric and optical sensors, and structural probes promise more-detailed views into neuronal signal propagation.
Department faculty are developing and testing heretofore unknown chemical reactions through virtual reality based molecular modeling kit that fully understands quantum dynamics. Seeking highly efficient classical simulation of problems at the interface of quantum and statistical mechanics, Stanford researchers are exploring multiple time-scale molecular dynamics approaches and targeted thermostat schemes.