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Sylvia T. Ceyer | |
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| Born | |
| Alma mater | Hope College University of California, Berkeley |
| Awards | Harold E. Edgerton Award (1988) Baker Memorial Award for Excellence in Undergraduate Teaching (1988) Contents |
| Scientific career | |
| Fields | Physical chemist |
| Institutions | NIST MIT |
Sylvia Teresse Ceyer is a professor of chemistry at MIT, holding the John C. Sheehan Chair in Chemistry. Until 2006, she held the chemistry chair of the National Academy of Sciences.
Ceyer graduated from Hope College in Holland, Michigan in 1974 with an A.B. in chemistry. [1] In 1979, she was awarded a Ph.D. in chemistry from the University of California, Berkeley. Her advisors were Y. T. Lee and Gabor Somorjai. She was a postdoctoral fellow at the National Bureau of Standards (now the National Institute of Standards and Technology) from 1979 to 1981.
Ceyer joined the MIT faculty in 1981. In 1987, she became tenured.
In 1994, Ceyer was one of 16 women faculty in the School of Science at MIT who drafted and co-signed a letter to the then-Dean of Science (now Chancellor of Berkeley) Robert Birgeneau, which started a campaign to highlight and challenge gender discrimination at MIT. [2]
In 2004, MIT was conducting a search for a new president, and she was appointed to the Faculty Advisory Committee to the MIT Corporation. The Corporation chose Susan Hockfield, a neurobiologist from Yale University to be MIT's next president.
The following year, she was appointed associate head of MIT's chemistry department.
On July 1, 2010, she became head of the chemistry department, saying "It is my goal to further the Department of Chemistry's commitment to outstanding chemical research and education as set by a long line of distinguished department heads and faculty." [3]
Ceyer is a physical chemist whose main research interests lie in the interactions of molecules with surfaces. This work is done in an ultra-high vacuum environment, because ambient gasses or liquids would otherwise modify the surface under study. This allows unambiguous identification of the reactive species and processes of interest. These surfaces can be templates for nanomechanical devices or catalysts for chemical reactions. The central theme to her work is understanding of the so-called "pressure-gap", the disparity observed between reactions that occur under high pressure and the corresponding lack of reaction observed under ultra-high vacuum conditions.
Her contributions to surface science include discovery of collision induced processes at surfaces, in which an energetic, neutral, noble gas atom impinges on a surface pre-covered with an adsorbate, causing a reaction to occur between the surface and the adsorbate. The reactions observed include dissociation, desorption, and absorption into the bulk of the substrate. In addition, she discovered that electron energy loss spectroscopy can be used to detect species absorbed in the bulk of a substrate, and can be used to differentiate between bulk and surface species. This paved the way for her discovery that hydrogen atoms absorbed in the bulk of a nickel sample are the key reactant in the hydrogenation of unsaturated hydrocarbons. Another major discovery involved the reaction of fluorine molecules with a silicon surface (a reaction that is key to semiconductor device etching), in which the silicon surface abstracts a fluorine atom from the incident fluorine molecule, and the remaining fluorine atom scatters into the gas phase. This is the reverse of the Eley-Rideal mechanism, one of the fundamental mechanism of gas-surface chemical reactions.
Prior to holding the John C. Sheehan Chair in Chemistry, Ceyer held the Class of 1943 Career Development Chair from 1985 to 1988 and the W. M. Keck Foundation Professorship in Energy from 1991 to 1996.
In 1988, she was awarded the Harold E. Edgerton Award, the Baker Memorial Award for Excellence in Undergraduate teaching and the Young Scholar Award from the American Association of University Women. In 1993, Ceyer was given the Nobel Laureate Signature Award from the American Chemical Society and the School of Science Teaching Prize. She was a MacVicar Faculty Fellow in 1998.
Ceyer is a fellow of the National Academy of Sciences, the American Physical Society and the American Academy of Arts and Sciences. She has held the Langmuir Lectureship of the American Chemical Society and the Welch Foundation Lectureship.
She was presented with the Willard Gibbs Award on May 26, 2007, for her research on heterogeneous catalysis.
William Nunn Lipscomb Jr. was a Nobel Prize-winning American inorganic and organic chemist working in nuclear magnetic resonance, theoretical chemistry, boron chemistry, and biochemistry.
In chemistry, hydronium (hydroxonium in traditional British English) is the common name for the aqueous cation H3O+, the type of oxonium ion produced by protonation of water. It is often viewed as the positive ion present when an Arrhenius acid is dissolved in water, as Arrhenius acid molecules in solution give up a proton (a positive hydrogen ion, H+) to the surrounding water molecules (H2O). In fact, acids must be surrounded by more than a single water molecule in order to ionize, yielding aqueous H+ and conjugate base. Three main structures for the aqueous proton have garnered experimental support: the Eigen cation, which is a tetrahydrate, H3O+(H2O)3, the Zundel cation, which is a symmetric dihydrate, H+(H2O)2, and the Stoyanov cation, an expanded Zundel cation, which is a hexahydrate: H+(H2O)2(H2O)4. Spectroscopic evidence from well-defined IR spectra overwhelmingly supports the Stoyanov cation as the predominant form. For this reason, it has been suggested that wherever possible, the symbol H+(aq) should be used instead of the hydronium ion.
Buckminsterfullerene is a type of fullerene with the formula C60. It has a cage-like fused-ring structure (truncated icosahedron) made of twenty hexagons and twelve pentagons, and resembles a football. Each of its 60 carbon atoms is bonded to its three neighbors.
Fluorocarbons are chemical compounds with carbon-fluorine bonds. Compounds that contain many C-F bonds often have distinctive properties, e.g., enhanced stability, volatility, and hydrophobicity. Several fluorocarbons and their derivatives are commercial polymers, refrigerants, drugs, and anesthetics.
In chemistry, noble gas compounds are chemical compounds that include an element from the noble gases, group 18 of the periodic table. Although the noble gases are generally unreactive elements, many such compounds have been observed, particularly involving the element xenon.
Mechanochemistry is the initiation of chemical reactions by mechanical phenomena. Mechanochemistry thus represents a fourth way to cause chemical reactions, complementing thermal reactions in fluids, photochemistry, and electrochemistry. Conventionally mechanochemistry focuses on the transformations of covalent bonds by mechanical force. Not covered by the topic are many phenomena: phase transitions, dynamics of biomolecules, and sonochemistry.
Adamantane is an organic compound with a formula C10H16 or, more descriptively, (CH)4(CH2)6. Adamantane molecules can be described as the fusion of three cyclohexane rings. The molecule is both rigid and virtually stress-free. Adamantane is the most stable isomer of C10H16. The spatial arrangement of carbon atoms in the adamantane molecule is the same as in the diamond crystal. This similarity led to the name adamantane, which is derived from the Greek adamantinos (relating to steel or diamond). It is a white solid with a camphor-like odor. It is the simplest diamondoid.
Arynes and benzynes are highly reactive species derived from an aromatic ring by removal of two substituents. Arynes are examples of didehydroarenes, although 1,3- and 1,4-didehydroarenes are also known. Arynes are examples of strained alkynes.
Xenon difluoride is a powerful fluorinating agent with the chemical formula XeF
2, and one of the most stable xenon compounds. Like most covalent inorganic fluorides it is moisture-sensitive. It decomposes on contact with water vapor, but is otherwise stable in storage. Xenon difluoride is a dense, colourless crystalline solid.
A Stone–Wales defect is a crystallographic defect that involves the change of connectivity of two π-bonded carbon atoms, leading to their rotation by 90° with respect to the midpoint of their bond. The reaction commonly involves conversion between a naphthalene-like structure into a fulvalene-like structure, that is, two rings that share an edge vs two separate rings that have vertices bonded to each other.
In chemistry and molecular physics, fluxionalmolecules are molecules that undergo dynamics such that some or all of their atoms interchange between symmetry-equivalent positions. Because virtually all molecules are fluxional in some respects, e.g. bond rotations in most organic compounds, the term fluxional depends on the context and the method used to assess the dynamics. Often, a molecule is considered fluxional if its spectroscopic signature exhibits line-broadening due to chemical exchange. In some cases, where the rates are slow, fluxionality is not detected spectroscopically, but by isotopic labeling and other methods.
Penning ionization is a form of chemi-ionization, an ionization process involving reactions between neutral atoms or molecules. The Penning effect is put to practical use in applications such as gas-discharge neon lamps and fluorescent lamps, where the lamp is filled with a Penning mixture to improve the electrical characteristics of the lamps.
This page deals with the electron affinity as a property of isolated atoms or molecules. Solid state electron affinities are not listed here.
The carbon–fluorine bond is a polar covalent bond between carbon and fluorine that is a component of all organofluorine compounds. It is one of the strongest single bonds in chemistry, and relatively short, due to its partial ionic character. The bond also strengthens and shortens as more fluorines are added to the same carbon on a chemical compound. As such, fluoroalkanes like tetrafluoromethane are some of the most unreactive organic compounds.
In chemistry, a water cluster is a discrete hydrogen bonded assembly or cluster of molecules of water. Many such clusters have been predicted by theoretical models (in silico), and some have been detected experimentally in various contexts such as ice, bulk liquid water, in the gas phase, in dilute mixtures with non-polar solvents, and as water of hydration in crystal lattices. The simplest example is the water dimer (H2O)2.
Melting-point depression is the phenomenon of reduction of the melting point of a material with a reduction of its size. This phenomenon is very prominent in nanoscale materials, which melt at temperatures hundreds of degrees lower than bulk materials.
James Bernhard Anderson was an American chemist and physicist. From 1995 to 2014 he was Evan Pugh Professor of Chemistry and Physics at the Pennsylvania State University. He specialized in Quantum Chemistry by Monte Carlo methods, molecular dynamics of reactive collisions, kinetics and mechanisms of gas phase reactions, and rare-event theory.
Calcium monohydride is a molecule composed of calcium and hydrogen with formula CaH. It can be found in stars as a gas formed when calcium atoms are present with hydrogen atoms.
Vincenzo Aquilanti is an Italian chemist, emeritus professor at the University of Perugia.
Graphene is the only form of carbon in which every atom is available for chemical reaction from two sides. Atoms at the edges of a graphene sheet have special chemical reactivity. Graphene has the highest ratio of edge atoms of any allotrope. Defects within a sheet increase its chemical reactivity. The onset temperature of reaction between the basal plane of single-layer graphene and oxygen gas is below 260 °C (530 K). Graphene combusts at 350 °C (620 K). Graphene is commonly modified with oxygen- and nitrogen-containing functional groups and analyzed by infrared spectroscopy and X-ray photoelectron spectroscopy. However, determination of structures of graphene with oxygen- and nitrogen- functional groups requires the structures to be well controlled.
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