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Lee SK, Yi Y, Kim YH, Kim HI, Chow P, Xiao Y, Eng P, Shen G. Imaging of the electronic bonding of diamond at pressures up to 2 million atmospheres. SCIENCE ADVANCES 2023; 9:eadg4159. [PMID: 37205753 DOI: 10.1126/sciadv.adg4159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 04/17/2023] [Indexed: 05/21/2023]
Abstract
Diamond shows unprecedented hardness. Because hardness is a measure of resistance of chemical bonds in a material to external indentation, the electronic bonding nature of diamond beyond several million atmospheres is key to understanding the origin of hardness. However, probing the electronic structures of diamond at such extreme pressure has not been experimentally possible. The measurements on the inelastic x-ray scattering spectra for diamond up to 2 million atmospheres provide data on the evolution of its electronic structures under compression. The mapping of the observed electronic density of states allows us to obtain a two-dimensional image of the bonding transitions of diamond undergoing deformation. The spectral change near edge onset is minor beyond a million atmospheres, while its electronic structure displays marked pressure-induced electron delocalization. Such electronic responses indicate that diamond's external rigidity is supported by its ability to reconcile internal stress, providing insights into the origins of hardness in materials.
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Affiliation(s)
- Sung Keun Lee
- School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Korea
- Institute of Applied Physics, Seoul National University, Seoul, Korea
| | - Yoosoo Yi
- School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Korea
| | - Yong-Hyun Kim
- School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Korea
| | - Hyo-Im Kim
- School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Korea
| | - Paul Chow
- HPCAT, X-ray Science Division, Argonne National Laboratory, Argonne, IL 60439 USA
| | - Yuming Xiao
- HPCAT, X-ray Science Division, Argonne National Laboratory, Argonne, IL 60439 USA
| | - Peter Eng
- Center for Advanced Radiation Sources, The University of Chicago, Chicago, IL 60637, USA
| | - Guoyin Shen
- HPCAT, X-ray Science Division, Argonne National Laboratory, Argonne, IL 60439 USA
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Li B, Ding Y, Kim DY, Wang L, Weng TC, Yang W, Yu Z, Ji C, Wang J, Shu J, Chen J, Yang K, Xiao Y, Chow P, Shen G, Mao WL, Mao HK. Probing the Electronic Band Gap of Solid Hydrogen by Inelastic X-Ray Scattering up to 90 GPa. PHYSICAL REVIEW LETTERS 2021; 126:036402. [PMID: 33543962 DOI: 10.1103/physrevlett.126.036402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/07/2020] [Accepted: 12/23/2020] [Indexed: 06/12/2023]
Abstract
Metallization of hydrogen as a key problem in modern physics is the pressure-induced evolution of the hydrogen electronic band from a wide-gap insulator to a closed gap metal. However, due to its remarkably high energy, the electronic band gap of insulating hydrogen has never before been directly observed under pressure. Using high-brilliance, high-energy synchrotron radiation, we developed an inelastic x-ray probe to yield the hydrogen electronic band information in situ under high pressures in a diamond-anvil cell. The dynamic structure factor of hydrogen was measured over a large energy range of 45 eV. The electronic band gap was found to decrease linearly from 10.9 to 6.57 eV, with an 8.6 times densification (ρ/ρ_{0}∼8.6) from zero pressure up to 90 GPa.
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Affiliation(s)
- Bing Li
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Yang Ding
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Duck Young Kim
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Lin Wang
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
- Center for High Pressure Science (CHiPS), State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, Hebei 066004, China
| | - Tsu-Chien Weng
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Wenge Yang
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Zhenhai Yu
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Cheng Ji
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
- HPCAT, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Junyue Wang
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Jinfu Shu
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
| | - Jiuhua Chen
- Center for the Study of Matter at Extreme Conditions, Department of Mechanical and Materials Engineering, Florida International University, Miami, Florida 33199, USA
| | - Ke Yang
- Shanghai Synchrotron Radiation Facility (SSRF), Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
| | - Yuming Xiao
- HPCAT, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Paul Chow
- HPCAT, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Guoyin Shen
- HPCAT, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Wendy L Mao
- Department of Geological Sciences, Stanford University, Stanford, California 94305, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Ho-Kwang Mao
- Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
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Guo Y, Cui L, Zhao D, Song T, Cui X, Liu Z. T-C 56: a low-density transparent superhard carbon allotrope assembled from C 16 cage-like cluster. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:165701. [PMID: 31896100 DOI: 10.1088/1361-648x/ab6710] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Owing to the various ways of chemical bonding, carbon can form abundant allotropes with different frameworks, which harbor rich mechanical and electronic properties. Taking the cage-like isomer of C16 cluster as a building block, we design a new low-density carbon allotrope, which has tetragonal symmetry (I4/mmm) and a 56-atom unit cell, hence termed as T-C56. Our first-principles calculations reveal that T-C56 is not only energetically, dynamically, thermally (above 1800 K) and mechanically stable, but even more stable than the experimentally synthesized C20-sc and T-carbon. Remarkably, although the framework of T-C56 is low density (2.72 g cm-3), it exhibits novel superhard properties with a Vickers hardness of 48.71 GPa. The obtained Yang's modulus and ideal strength show that T-C56 is mechanically anisotropic. In particular, our analysis of electronic and optical properties suggest that T-C56 is a transparent indirect semiconductor with a wide bandgap of 3.18 eV (HSE06). These findings highlight a distinct carbon allotrope, having promising applications for optical and aerospace devices due to its light, transparent, superhard features.
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O'Bannon EF, Jenei Z, Cynn H, Lipp MJ, Jeffries JR. Contributed Review: Culet diameter and the achievable pressure of a diamond anvil cell: Implications for the upper pressure limit of a diamond anvil cell. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:111501. [PMID: 30501343 DOI: 10.1063/1.5049720] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 10/14/2018] [Indexed: 06/09/2023]
Abstract
Recently, static pressures of more than 1.0 TPa have been reported, which raises the question: what is the maximum static pressure that can be achieved using diamond anvil cell techniques? Here we compile culet diameters, bevel diameters, bevel angles, and reported pressures from the literature. We fit these data and find an expression that describes the maximum pressure as a function of the culet diameter. An extrapolation of our fit reveals that a culet diameter of 1 μm should achieve a pressure of ∼1.8 TPa. Additionally, for pressure generation of ∼400 GPa with a single beveled diamond anvil, the most commonly reported parameters are a culet diameter of ∼20 μm, a bevel angle of 8.5°, and a bevel diameter to culet diameter ratio between 14 and 18. Our analysis shows that routinely generating pressures more than ∼300 GPa likely requires diamond anvil geometries that are fundamentally different from a beveled or double beveled anvil (e.g., toroidal or double stage anvils) and culet diameters that are ≤20 μm.
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Affiliation(s)
- Earl F O'Bannon
- Physical and Life Sciences, Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94551, USA
| | - Zsolt Jenei
- Physical and Life Sciences, Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94551, USA
| | - Hyunchae Cynn
- Physical and Life Sciences, Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94551, USA
| | - Magnus J Lipp
- Physical and Life Sciences, Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94551, USA
| | - Jason R Jeffries
- Physical and Life Sciences, Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94551, USA
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Baimova JA, Rysaeva LK. Deformation Behavior of Three-Dimensional Carbon Structures Under Hydrostatic Compression. J STRUCT CHEM+ 2018. [DOI: 10.1134/s0022476618040200] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Jenei Z, O'Bannon EF, Weir ST, Cynn H, Lipp MJ, Evans WJ. Single crystal toroidal diamond anvils for high pressure experiments beyond 5 megabar. Nat Commun 2018; 9:3563. [PMID: 30177697 PMCID: PMC6120914 DOI: 10.1038/s41467-018-06071-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 08/10/2018] [Indexed: 11/19/2022] Open
Abstract
Static compression experiments over 4 Mbar are rare, yet critical for developing accurate fundamental physics and chemistry models, relevant to a range of topics including modeling planetary interiors. Here we show that focused ion beam crafted toroidal single-crystal diamond anvils with ~9.0 μm culets are capable of producing pressures over 5 Mbar. The toroidal surface prevents gasket outflow and provides a means to stabilize the central culet. We have reached a maximum pressure of ~6.15 Mbar using Re as in situ pressure marker, a pressure regime typically accessed only by double-stage diamond anvils and dynamic compression platforms. Optimizing single-crystal diamond anvil design is key for extending the pressure range over which studies can be performed in the diamond anvil cell. Static pressures exceeding 4 million atmospheres are extremely challenging to achieve, but are necessary for the study of matter that exists under these conditions in natural environments. Here, diamonds anvils with a toroidal design are demonstrated to sustain over 6 million atmospheres in a diamond anvil cell.
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Affiliation(s)
- Zs Jenei
- Physics Division, Physical & Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94551, USA.
| | - E F O'Bannon
- Physics Division, Physical & Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94551, USA
| | - S T Weir
- Physics Division, Physical & Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94551, USA
| | - H Cynn
- Physics Division, Physical & Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94551, USA
| | - M J Lipp
- Physics Division, Physical & Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94551, USA
| | - W J Evans
- Physics Division, Physical & Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94551, USA
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Abstract
The structure, bonding, and other properties of phases in the carbon-hydrogen system over a range of conditions are of considerable importance to a broad range of scientific problems. However, the phase diagram of the C-H system at high pressures and temperatures is still not known. To search for new low-energy hydrocarbon structures, we carried out systematic structure prediction calculations for the C-H system from 100 to 300 GPa. We confirmed several previously predicted structures but found additional compositions that adopt more stable structures. In particular, a C2H4 structure is found that has an indirect band gap, and phonon calculations confirm that it is dynamically stable over a broad pressure range. We also identify more carbon-rich structures that are energetically favorable. The results are important for understanding carbon-hydrogen interactions in high-pressure experiments, dense astrophysical environments and the deep carbon cycle in planetary interiors.
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Affiliation(s)
- Hanyu Liu
- Geophysical Laboratory, Carnegie Institution of Washington , Washington, D.C. 20015, United States
| | - Ivan I Naumov
- Geophysical Laboratory, Carnegie Institution of Washington , Washington, D.C. 20015, United States
| | - Russell J Hemley
- Department of Civil and Environmental Engineering, The George Washington University , Washington, D.C. 20052 United States
- Lawrence Livermore National Laboratory , Livermore, California 94550 United States
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Phase transformations in materials studied by micro-Raman spectroscopy of indentations. ACTA ACUST UNITED AC 2016. [DOI: 10.1007/s100190050011] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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10
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Constitutive law and flow mechanism in diamond deformation. Sci Rep 2012; 2:876. [PMID: 23166859 PMCID: PMC3500768 DOI: 10.1038/srep00876] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 10/30/2012] [Indexed: 11/09/2022] Open
Abstract
Constitutive laws and crystal plasticity in diamond deformation have been the subjects of substantial interest since synthetic diamond was made in 1950's. To date, however, little is known quantitatively regarding its brittle-ductile properties and yield strength at high temperatures. Here we report, for the first time, the strain-stress constitutive relations and experimental demonstration of deformation mechanisms under confined high pressure. The deformation at room temperature is essentially brittle, cataclastic, and mostly accommodated by fracturing on {111} plane with no plastic yielding at uniaxial strains up to 15%. At elevated temperatures of 1000°C and 1200°C diamond crystals exhibit significant ductile flow with corresponding yield strength of 7.9 and 6.3 GPa, indicating that diamond starts to weaken when temperature is over 1000°C. At high temperature the plastic deformation and ductile flow is meditated by the <110>{111} dislocation glide and a very active {111} micro-twinning.
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Zha CS, Liu Z, Hemley RJ. Synchrotron infrared measurements of dense hydrogen to 360 GPa. PHYSICAL REVIEW LETTERS 2012; 108:146402. [PMID: 22540811 DOI: 10.1103/physrevlett.108.146402] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2011] [Indexed: 05/31/2023]
Abstract
Diamond-anvil-cell techniques have been developed to confine and measure hydrogen samples under static conditions to pressures above 300 GPa from 12 to 300 K using synchrotron infrared and optical absorption techniques. A decreasing absorption threshold in the visible spectrum is observed, but the material remains transparent at photon energies down to 0.1 eV at pressures to 360 GPa over a broad temperature range. The persistence of the strong infrared absorption of the vibron characteristic of phase III indicates the stability of the paired state of hydrogen. There is no evidence for the predicted metallic state over these conditions, in contrast to recent reports, but electronic properties consistent with semimetallic behavior are observed.
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Affiliation(s)
- Chang-Sheng Zha
- Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington, DC 20015, USA
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12
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Enhanced optical properties of chemical vapor deposited single crystal diamond by low-pressure/high-temperature annealing. Proc Natl Acad Sci U S A 2008; 105:17620-5. [PMID: 19004770 DOI: 10.1073/pnas.0808230105] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Single crystal diamond produced by chemical vapor deposition (CVD) at very high growth rates (up to 150 microm/h) has been successfully annealed without graphitization at temperatures up to 2200 degrees C and pressures <300 torr. Crystals were annealed in a hydrogen environment by using microwave plasma techniques for periods of time ranging from a fraction of minute to a few hours. This low-pressure/high-temperature (LPHT) annealing enhances the optical properties of this high-growth rate CVD single crystal diamond. Significant decreases are observed in UV, visible, and infrared absorption and photoluminescence spectra. The decrease in optical absorption after the LPHT annealing arises from the changes in defect structure associated with hydrogen incorporation during CVD growth. There is a decrease in sharp line spectral features indicating a reduction in nitrogen-vacancy-hydrogen (NVH(-)) defects. These measurements indicate an increase in relative concentration of nitrogen-vacancy (NV) centers in nitrogen-containing LPHT-annealed diamond as compared with as-grown CVD material. The large overall changes in optical properties and the specific types of alterations in defect structure induced by this facile LPHT processing of high-growth rate single-crystal CVD diamond will be useful in the creation of diamond for a variety of scientific and technological applications.
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Baer BJ, Evans WJ, Yoo CS. Coherent anti-stokes Raman spectroscopy of highly compressed solid deuterium at 300 K: evidence for a new phase and implications for the band gap. PHYSICAL REVIEW LETTERS 2007; 98:235503. [PMID: 17677917 DOI: 10.1103/physrevlett.98.235503] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Indexed: 05/16/2023]
Abstract
Coherent anti-Stokes Raman spectroscopy has been used to study deuterium at ambient temperature to 187 GPa, the highest pressure this technique has ever been applied. The pressure dependence of the nu1 vibron line shape indicates that deuterium has a rho direct=0.501 and rho exciton=0.434 mol/cm3 for a band gap of 2omega P=4.66 eV. The extrapolation from the ambient pressure band gap yields a metallization pressure of 460 GPa, confirming earlier measurements. Above 143 GPa, the Raman shift data provide clear evidence for the presence of the ab initio predicted I' phase of deuterium.
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Affiliation(s)
- Bruce J Baer
- H-Division, Physics & Advanced Technologies, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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Bradley DK, Eggert JH, Hicks DG, Celliers PM, Moon SJ, Cauble RC, Collins GW. Shock compressing diamond to a conducting fluid. PHYSICAL REVIEW LETTERS 2004; 93:195506. [PMID: 15600850 DOI: 10.1103/physrevlett.93.195506] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2004] [Indexed: 05/24/2023]
Abstract
Laser generated shock reflectance data show that diamond undergoes a continuous transition from optically absorbing to reflecting between Hugoniot pressures 600<P(H)<1000 GPa. The data are consistent with diamond having a thermal population of carriers at P(H) approximately 600 GPa, undergoing band overlap metallization at P(H) approximately 1000 GPa and melting at 800<P(H)<1000 GPa. The results agree well with an equation of state model that predicts that elemental carbon remains solid throughout the interior of Neptune.
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Affiliation(s)
- D K Bradley
- Lawrence Livermore National Laboratory, Livermore, California 94551, USA
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Occelli F, Loubeyre P, LeToullec R. Properties of diamond under hydrostatic pressures up to 140 GPa. NATURE MATERIALS 2003; 2:151-154. [PMID: 12612670 DOI: 10.1038/nmat831] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2002] [Accepted: 01/06/2003] [Indexed: 05/24/2023]
Abstract
Diamond is the archetypal covalent material. Each atom in an sp(3) configuration is bonded to four nearest neighbours. Because of its remarkable properties, diamond has been extensively studied. And yet our knowledge of the properties of diamond under very high pressure is still incomplete. Although diamond is known to be the preferred allotrope of carbon at high pressure, the possibility of producing under pressure high-density polymorphs of diamond, including metallic forms, has been discussed. Structural changes have already been reported in diamond under non-hydrostatic pressures around 150 GPa and large deformation. However, measurements of the properties of diamond under hydrostatic pressure have been limited to below 40 GPa. Here, we report accurate measurements of the volume and of the optical phonon frequency of diamond under hydrostatic pressure up to 140 GPa. We show that diamond is more compressible than currently expected. By combining the volume and the frequency pressure shifts, we deduce that diamond remains very stable under pressure: it is a Gruneisen solid up to at least 140 GPa, and the covalent bond is even slightly strengthened under pressure. Finally, the optical phonon frequency versus pressure is calibrated here to be used as a pressure gauge for diamond anvil cell studies in the multi-megabar range.
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Affiliation(s)
- Florent Occelli
- Département de Physique Théorique et Appliquée, CEA/DAM/DIF, 91680 Bruyères-le-Châtel, France
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Goncharov AF, Gregoryanz E, Hemley RJ, Mao H. Spectroscopic studies of the vibrational and electronic properties of solid hydrogen to 285 GPa. Proc Natl Acad Sci U S A 2001; 98:14234-7. [PMID: 11717391 PMCID: PMC64665 DOI: 10.1073/pnas.201528198] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We report Raman scattering and visible to near-infrared absorption spectra of solid hydrogen under static pressure up to 285 GPa between 20 and 140 K. We obtain pressure dependences of vibron and phonon modes consistent with results previously determined to lower pressures. The results indicate the stability of the ordered molecular phase III to the highest pressure reached and provide constraints on the insulator-to-metal transition pressure.
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Affiliation(s)
- A F Goncharov
- Geophysical Laboratory and Center for High Pressure Research, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington, DC 20015, USA
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Hemley RJ, Mao H, Goncharov AF, Hanfland M, Struzhkin V. Synchrotron infrared spectroscopy to 0.15 eV of H2 and D2 at megabar pressures. PHYSICAL REVIEW LETTERS 1996; 76:1667-1670. [PMID: 10060487 DOI: 10.1103/physrevlett.76.1667] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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20
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Scandolo S, Chiarotti GL, Tosatti E. SC4: A metallic phase of carbon at terapascal pressures. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:5051-5054. [PMID: 9984087 DOI: 10.1103/physrevb.53.5051] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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21
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Hanfland M, Hemley RJ, Mao H. Reply to "Comment on 'Optical absorption measurements of hydrogen at megabar pressures' ". PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 52:1408-1410. [PMID: 9980723 DOI: 10.1103/physrevb.52.1408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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22
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Loubeyre P, Letoullec R, Pinceaux JP. Compression of Ar(H2)2 up to 175 GPa: A new path for the dissociation of molecular hydrogen? PHYSICAL REVIEW LETTERS 1994; 72:1360-1363. [PMID: 10056693 DOI: 10.1103/physrevlett.72.1360] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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23
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Hemley RJ, Eggert JH, Mao H. Low-frequency Raman spectroscopy of deuterium to megabar pressures at 77-295 K. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:5779-5788. [PMID: 10009110 DOI: 10.1103/physrevb.48.5779] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Hanfland M, Hemley RJ, Mao H. Novel infrared vibron absorption in solid hydrogen at megabar pressures. PHYSICAL REVIEW LETTERS 1993; 70:3760-3763. [PMID: 10053955 DOI: 10.1103/physrevlett.70.3760] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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25
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Mao HK, Hemley RJ, Hanfland M. Stability of ruby in solid hydrogen at megabar pressures. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:8108-8111. [PMID: 10000624 DOI: 10.1103/physrevb.45.8108] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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