Faculty of Chemistry

 

Dean: Yehiam Prior
The Sherman Professorial Chair of Physical Chemistry

Department of Chemical Physics

The department consists of theoreticians and experimentalists working at the interface between physics and chemistry. The experimental research is focused, in general, on the understanding of the interaction of matter with different kinds of radiation or charged particles. The effect of the chemical environment on this interaction is investigated by methods such as magnetic resonance, laser spectroscopy, electron tunneling, and electron transmission. New experimental techniques are developed and then applied to a variety of problems in chemistry, physics and biophysics such as catalysis, dynamics of molecules in confined space, enzymatic reactions, the study of protein folding through single molecule spectroscopy, and the study of molecules as possible candidates for electronic devices. The manipulation of chemical reactions by lasers is studied both theoretically and experimentally and the effect of strong laser fields on matter is probed. Extensive theoretical research is also devoted to the complexity of nature and non linear dynamics, reaction dynamics in condensed matter, electron transfer reaction in solutions and quantum optics.

Department of Environmental Sciences and Energy Research

The research at the department is focused on understanding the complex inter - relationships among the major Earth systems and between the human need for alternative energy source and the consequent impact on the Earth's environment. The efforts are equally split between field/experimental work and theoretical studies.

The research into climate change and the atmospheric greenhouse effect takes several directions, including climate dynamics, oceanic circulation, paleoceanography and the study of past climatic patterns, plant-environment interaction and atmospheric chemistry, earth system dynamics and geophysics. These topics are studies as the basic means to understand and predict global changes.

In Hydrology, the research activity has centered on combination of field and laboratory studies with theoretical models to understand flow of water and chemicals from the ground surface, through the unsaturated zone into the geological saturated formations.

The Solar Energy research is focused on all aspects of using concentrated solar light. It includes the development of new hybrid solar thermal systems, solar fuels, concentrated photovoltaic systems and solar lasers. A technology transfer to the industry was initiated as a result of this work.

Our main objective for the future is to develop scientific activities based on experimental studies providing the basis for integration of field observations into mathematical models. The dynamic of the atmosphere and the lithosphere, environmental analytical chemistry, field hydrology, eco-physiology and climate prediction are among the main fields that we want to develop in the near future.

Department of Materials and Interfaces

The Department of Materials and Interfaces of the Weizmann Institute of Science is an interdisciplinary scientific unit composed of physicists, chemists and materials scientists. A common theme of much of the research done in the department is the design of materials from elementary units with unique, pre-designed functionality. A complementary effort involves the understanding of the functionality of various materials, based on their supramolecular architecture. This leads naturally to foussing on nanomaterials, from synthesis to characterization and eventually to their applications in variety of fields. In addition to new insights in how materials properties can be understood from their atomic, molecular and macromolecular composition and structure, this strategy permits the development of new high performance materials and nanocomposites for numerous applications.

Some recent accomplishments include: a monolayer of water molecules squeezed between two mica surfaces coated with polymer molecules was shown to provide an extremely low friction coefficient, which is relevant to bio-lubrication. A new kind of 1D solid consisting of an ordered array of bubbles flowing in a microfluidic channel was discovered and its highly damped sound wave velocity and phonon spectra were measured. A new torsional nanoelectromechanical device based on carbon nanotubes was fabricated. This device was found to exhibit quantum current oscillations.

Research in the Department of Organic Chemistry

The areas of research in the Department of Organic Chemistry include synthetic and mechanistic organic, inorganic and organometallic chemistry involving novel reactions for organic synthesis; syntheses of physiologically active compounds; polymeric reagents; bond activation studies; homogeneous catalysis by specifically designed metal complexes; selective oxidation catalysis by polyoxometalates; creation of organic films with desirable electronic and optical properties and the development of molecule-based technologies. Bioorganic chemistry includes the studies of plant antiviral agents; the molecular mechanism of action of rhodopsin; artificial ion carriers and molecular sensors. Biological chemistry includes studies on structure, function, and mode of action of biologically active peptides and proteins; thermophilic enzymes; enzymes involved in DNA repair, DNA and RNA processing; and studies of ordered, compact states of nucleic acids. Methods for very accurate ab initio calculations of molecular properties are being developed and applied.

Department of Structural Biology

The Department is committed to research in the major areas of structural biology and is investigating biological systems from the atomic to the cellular level of organization. The ultimate goal is to obtain a complete picture of biological structures in their complexity, with a continuity at all length scales, from Angstroms to millimetres. The structures of biological macromolecules and their complexes are studied at the length scale of Angstroms by X-ray diffraction from crystals, and in solution by advanced spectroscopic techniques such as nuclear magnetic resonance and EXAFS. Electron microscopy, electron tomography and atomic force miscroscopy are imaging techniques used that span the range between nanometers and microns, i.e. from single molecules to macromolecular assemblies and whole tissue organization.

The elucidation of the relations between structure and function of key components in main biological pathways is one of the generalized goals of the research conducted in the Department. One such pathway is the translation of the genetic code from DNA to proteins. A highlight in recent years has been the continued progress in determination of different structures of the ribosome and their complexes with substrate analogues, cofactors, chaperones or antibiotics. These most significant achievements crown the titanic efforts of tens of years of research aimed at elucidating the structure and mechanism of action of ribosomes which are the principal protein synthesis machinery of the cell. Additional research in this area includes structural studies on transcription factors and their DNA targets, tRNA synthetases and their complexes with various substrates, and helicases that unwind RNA Work is also being carried out on chaperones and enzymes that catalyze disulfide bridge formation. These factors assist protein folding which constitutes one of the last 'steps' in the pathway from DNA to functional proteins. The physical principles of protein folding and other biomolecular self-assembly processes (such as protein-protein and protein-DNA recognition) are investigated by using a variety of computational and theoretical tools.

Structural and dynamical aspects of enzyme and protein function and recognition constitute another focal point of activity. Examples are studies on the mechanism of acetylcholinesterase, a key enzyme in the transmission of nerve impulses, on proteins regulating membrane-fusion and virus entry into the cell and on metalloproteins. Antibody-antigen recognition is studied using NMR and the tools of molecular biology to unravel the energetic contributions of single interactions, and through antibodies interacting with monolayer and crystal surfaces.

Studies on the relations between organic and mineral components and between structure, function and mechanical properties of mineralised tissues including bone, teeth and shells, and on the nanomechanics of hearing, are performed over the whole range of hierarchical organizations. The development of new techniques in archeological chemistry provides information about human life conditions and technologies in prehistoric times .

The X-ray and NMR facilities are now state-of-the-art. A major upgrade in the electron microscopy facility has also taken place with the addition of two high resolution transmission electron microscopes, an environmental field emission scanning electron microscope, and a high-resolution SEM.

http://www.weizmann.ac.il/chemistry/