Dave Mao’s research centers on ultra-high pressure physics, chemistry, material sciences, geophysics, geochemistry and planetary sciences using diamond-anvil cell techniques that he has pioneered. He is also director of the Energy Frontier Research in Extreme Environments (EFree) center at the Geophysical Laboratory and he is director of the High Pressure Synergitic Center (HPSynC) and the High Pressure Collaborative Access Team (HPCAT) at the Advanced Photon Source, Argonne National Laboratory, IL.

Mao pioneered the diamond anvil cell, an instrument designed to subject materials to high pressures and temperatures by squeezing matter between two diamond tips. Over the years Mao has improved on both the diamond anvil cell and measurement instrumentation that reveals the properties of materials as they undergo extreme conditions. He has made many important discoveries about the chemical, structural, and other physical characteristics of matter along the way. 

In one study, Mao and colleagues subjected a mixture of hydrogen and water to a pressure of about 220 megapascals (2,000 times  atmospheric pressure) at room temperature (300 K or 80°F), which formed a clathrate hydrate—a cage-like framework of water molecules enclosing molecules of gas. Unlike most clathrate hydrates, where only one molecule of a gas can be trapped in each of the H2O cages, multiple hydrogen molecules were entrapped in this material. This finding may be important to the development of hydrogen storage devices—a prerequisite to using hydrogen as fuel.

In another study Mao and colleagues transformed graphite, the soft “lead” of pencils, into a material that competes in strength with its molecular cousin diamond. Mao also explores what happens to elements in planetary cores. He is looking at defining thermodynamic, elastic, and vibrational parameters of elements such as iron and hydrogen at core conditions. This work is important to basic research and for understanding seismological phenomena.

Mao received a B.Sc. in geology from National University in Taiwan, China in 1963. He received a MS.c. and  Ph.D. from the University of Rochester in 1966 and 1968. Between 19968 and 1972 he was a postdoctoral fellow and research associate at Carnegie. He was appointed staff scientist in 1972. For more information see here

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August 30, 2017

Washington, DC— A team of Carnegie high-pressure physicists have created a form of carbon that’s hard as diamond, but amorphous, meaning it lacks the large-scale structural repetition of a diamond’s crystalline structure. Their findings are reported in Nature Communications.

Carbon is an element of seemingly infinite possibilities, because the configuration of its electrons allows for numerous self-bonding combinations that give rise to a range of materials with varying properties.

For example, some forms of carbon, such as coal, are what’s called amorphous, meaning that they lack the long-range repetitive structure that makes up a crystal.

Other forms of carbon are

August 1, 2017

The Geophysical Laboratory’s Postdoctoral Associate Zachary Geballe has been honored with Carnegie’s seventh Postdoctoral Innovation and Excellence (PIE) Award. These prizes are made through nominations from the departments and are chosen by the Office of the President. Geballe, in Viktor Struzhkin’s lab, was awarded the prize for his scientific innovations and community service to the Broad Branch Road (BBR) campus.

Zack works on developing methods to measure the heat capacities of metals and silicates at high pressures. This work applies to developing new materials and studying the deep interiors of planets.   He developed a pioneering technique to measure heat in a diamond

Carnegie Science, Carnegie Institution, Carnegie Institution for Science, University of Bristol
July 13, 2017

Washington, DC— Experimental petrologist Michael Walter, currently head of the School of Earth Sciences at the University of Bristol, has been selected as the eighth director of Carnegie’s Geophysical Laboratory.  He will begin his directorship on April 1, 2018.  

Walter has been at Bristol since 2004 and began a five-year term as head of school in 2013. He received his PhD in geology and Earth science from the University of Texas, Dallas, and a Bachelor of Science in the same from the University of Nebraska, Omaha. Early in his career, Walter was a postdoctoral fellow at the Geophysical Laboratory, so his new role is a homecoming.

Walter’s recent research has focused on

Carnegie Science, Carnegie Institution, Carnegie Institution for Science, Tim Strobel
June 9, 2017

Washington, DC— A team including several Carnegie scientists has developed a form of ultrastrong, lightweight carbon that is also elastic and electrically conductive. A material with such a unique combination of properties could serve a wide variety of applications from aerospace engineering to military armor.

Carbon is an element of seemingly infinite possibilities. This is because the configuration of its electrons allows for numerous self-bonding combinations that give rise to a range of materials with varying properties. For example, transparent, superhard diamonds, and opaque graphite, which is used for both pencils and industrial lubricant, are comprised solely of carbon.

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The High Pressure Collaborative Access Team (HPCAT) was established to advance cutting-edge, multidisciplinary, high-pressure science and technology using synchrotron radiation at the Advanced Photon Source (APS) of Argonne National Laboratory in Illinois.

The integrated HPCAT facility has established four operating beamlines in nine hutches An array of novel X-ray diffraction—imaging at tiny scales--and spectroscopic techniques to reveal chemistry,  has been integrated with high pressure and extreme temperature instrumentation.

With a multidisciplinary approach and multi-institution collaborations, the high-pressure program at the HPCAT has enabeld myriad scientific

CDAC is a multisite, interdisciplinary center headquartered at Carnegie to advance and perfect an extensive set of high pressure and temperature techniques and facilities, to perform studies on a broad range of materials in newly accessible pressure and temperature regimes, and to integrate and coordinate static, dynamic and theoretical results. The research objectives include making highly accurate measurements to understand the transitions of materials into different phases under the multimegabar pressure rang; determine the electronic and magnetic properties of solids and fluid to multimegabar pressures and elevated temperatures; to bridge the gap between static and dynamic

The Energy Frontier Research in Extreme Environments Center (EFree) was established to accelerate the discovery and synthesis of kinetically stabilized, energy-related materials using extreme conditions. Partners in this Carnegie-led center include world-leading groups in five universities—Caltech, Cornell, Penn State, Lehigh, and Colorado School of Mines—and will use facilities built and managed by the Geophysical Laboratory at Argonne, Brookhaven, and Oak Ridge National Laboratories. Nine Geophysical Laboratory scientists will participate in the effort, along with Russell Hemley as director and Tim Strobel as associate director.

To achieve their goal, EFree personnel synthesize

The Geophysical Laboratory has made important advances in the growth of diamond by chemical vapor deposition (CVD).  Methods have been developed to produce single-crystal diamond at low pressure having a broad range of properties.

Guillermo Blanc wants to understand the processes by which galaxies form and evolve over the course of the history of the universe. He studies local galaxies in the “present day” universe as well as very distant and therefore older galaxies to observe the early epochs of galaxy evolution. Blanc conducts a series of research projects on the properties of young and distant galaxies, the large-scale structure of the universe, the nature of Dark Energy—the mysterious repulsive force, the process of star formation at galactic scales, and the measurement of chemical abundances in galaxies.

To conduct this work, he takes a multi-wavelength approach including observations in the UV,

Peter van Keken studies the thermal and chemical evolution of the Earth. In particularly he looks at the causes and consequences of plate tectonics; element modeling of mantle convection,  and the dynamics of subduction zones--locations where one tectonic plate slides under another. He also studies mantle plumes; the integration of geodynamics with seismology; geochemistry and mineral physics. He uses parallel computing and scientific visualization in this work.

He received his BS and Ph D from the University of Utrecht in The Netherlands. Prior to joining Carnegie he was on the faculty of the University of Michigan.

Peter Driscoll studies the evolution of Earth’s core and magnetic field including magnetic pole reversal. Over the last 20 million or so years, the north and south magnetic poles on Earth have reversed about every 200,000, to 300,000 years and is now long overdue. He also investigates the Earth’s inner core structure; core-mantle coupling; tectonic-volatile cycling; orbital migration—how Earth’s orbit moves—and tidal dissipation—the dissipation of tidal forces between two closely orbiting bodies. He is also interested in planetary interiors, dynamos, upper planetary atmospheres and exoplanets—planets orbiting other stars. He uses large-scale numerical simulations in much of his research

Andrew Newman works in several areas in extragalactic astronomy, including the distribution of dark matter--the mysterious, invisible  matter that makes up most of the universe--on galaxies, the evolution of the structure and dynamics of massive early galaxies including dwarf galaxies, ellipticals and cluster. He uses tools such as gravitational lensing, stellar dynamics, and stellar population synthesis from data gathered from the Magellan, Keck, Palomar, and Hubble telescopes.

Newman received his AB in physics and mathematics from the Washington University in St. Louis, and his MS and Ph D in astrophysics from Caltech. Before becomming a staff astronomer in 2015, he was a