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Scelta D, Ceppatelli M, Bini R, Pakhomova A, Garbarino G, Mezouar M, Santoro M. High temperature decomposition of polymeric carbon monoxide at pressures up to 120 GPa. J Chem Phys 2023; 159:084501. [PMID: 37610022 DOI: 10.1063/5.0157907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 08/01/2023] [Indexed: 08/24/2023] Open
Abstract
While polymeric carbon monoxide (pCO) has been experimentally found to remain amorphous and undecomposed at room temperature up to 50 GPa, the question of whether crystalline counterparts of it can be obtained naturally raises. From different computational studies, it can be inferred that either the crystallization of amorphous pCO (a-pCO) or its decomposition into a mixture of CxOy suboxides (x > y) or carbon and CO2 may occur. In this study, we report experimental investigations of the high temperature (700-4000 K) transformation of a-pCO in the 47-120 GPa pressure range, conducted by x-ray diffraction in laser heated diamond anvil cells. Our results show the formation of no crystalline phases other than CO2 phase V, thus indicating the decomposition of the pristine a-pCO into CO2 and, likely, a mixture of amorphous CxOy suboxides and amorphous carbon hardly detectable at extreme conditions. These results support the theoretical picture of the pCO decomposition. We also show that the pressure-temperature kinetic border for this decomposition is very steep, thus indicating a strongly pressure-dependent kinetic barrier.
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Affiliation(s)
- Demetrio Scelta
- European Laboratory for Nonlinear Spectroscopy, LENS, Via Nello Carrara 1, 50019 Sesto Fiorentino (FI), Italy
- Consiglio Nazionale delle Ricerche-Istituto di Chimica dei Composti OrganoMetallici, CNR-ICCOM, Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy
| | - Matteo Ceppatelli
- European Laboratory for Nonlinear Spectroscopy, LENS, Via Nello Carrara 1, 50019 Sesto Fiorentino (FI), Italy
- Consiglio Nazionale delle Ricerche-Istituto di Chimica dei Composti OrganoMetallici, CNR-ICCOM, Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy
| | - Roberto Bini
- European Laboratory for Nonlinear Spectroscopy, LENS, Via Nello Carrara 1, 50019 Sesto Fiorentino (FI), Italy
- Consiglio Nazionale delle Ricerche-Istituto di Chimica dei Composti OrganoMetallici, CNR-ICCOM, Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy
- Dipartimento di Chimica "Ugo Schiff," Università di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy
| | - Anna Pakhomova
- European Synchrotron Radiation Facility, ESRF, 71 Avenue des Martyrs, CS40220, 38043 Grenoble Cedex 9, France
| | - Gaston Garbarino
- European Synchrotron Radiation Facility, ESRF, 71 Avenue des Martyrs, CS40220, 38043 Grenoble Cedex 9, France
| | - Mohamed Mezouar
- European Synchrotron Radiation Facility, ESRF, 71 Avenue des Martyrs, CS40220, 38043 Grenoble Cedex 9, France
| | - Mario Santoro
- European Laboratory for Nonlinear Spectroscopy, LENS, Via Nello Carrara 1, 50019 Sesto Fiorentino (FI), Italy
- Consiglio Nazionale delle Ricerche-Istituto Nazionale di Ottica, CNR-INO, Via Nello Carrara 1, 50019 Sesto Fiorentino (FI), Italy
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2
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Yan J, Tóth O, Xu W, Liu XD, Gregoryanz E, Dalladay-Simpson P, Qi Z, Xie S, Gorelli F, Martoňák R, Santoro M. High-Pressure Structural Evolution of Disordered Polymeric CS 2. J Phys Chem Lett 2021; 12:7229-7235. [PMID: 34310154 DOI: 10.1021/acs.jpclett.1c01762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Carbon disulfide is an archetypal double-bonded molecule belonging to the class of group IV-group VI, AB2 compounds. It is widely believed that, upon compression to several GPa at room temperature and above, a polymeric chain of type (-(C═S)-S-)n, named Bridgman's black polymer, will form. By combining optical spectroscopy and synchrotron X-ray diffraction data with ab initio simulations, we demonstrate that the structure of this polymer is different. Solid molecular CS2 polymerizes at ∼10-11 GPa. The polymer is disordered and consists of a mixture of 3-fold (C3) and 4-fold (C4) coordinated carbon atoms with some C═C double bonds. The C4/C3 ratio continuously increases upon further compression to 40 GPa. Upon decompression, structural changes are partially reverted, while the sample also undergoes partial disproportionation. Our work uncovers the nontrivial high-pressure structural evolution in one of the simplest molecular systems exhibiting molecular as well as polymeric phases.
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Affiliation(s)
- Jinwei Yan
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China
- University of Science and Technology of China, Hefei 230026, China
- Center for High Pressure Science and Technology Advanced Research, 1690 Cailun Road, Shanghai, 201203, China
| | - Ondrej Tóth
- Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava, Mlynská Dolina F2, 842 48 Bratislava, Slovakia
| | - Wan Xu
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China
- University of Science and Technology of China, Hefei 230026, China
| | - Xiao-Di Liu
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China
| | - Eugene Gregoryanz
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China
- Center for High Pressure Science and Technology Advanced Research, 1690 Cailun Road, Shanghai, 201203, China
- School of Physics and Astronomy and Centre for Science at Extreme Conditions, University of Edinburgh, Edinburgh EH9 3JZ, U.K
| | - Philip Dalladay-Simpson
- Center for High Pressure Science and Technology Advanced Research, 1690 Cailun Road, Shanghai, 201203, China
| | - Zeming Qi
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China
| | - Shiyu Xie
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China
| | - Federico Gorelli
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China
- Center for High Pressure Science and Technology Advanced Research, 1690 Cailun Road, Shanghai, 201203, China
- Istituto Nazionale di Ottica (CNR-INO) and European Laboratory for non Linear Spectroscopy (LENS), via N. Carrara 1, 50019 Sesto Fiorentino, Italy
| | - Roman Martoňák
- Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava, Mlynská Dolina F2, 842 48 Bratislava, Slovakia
| | - Mario Santoro
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China
- Istituto Nazionale di Ottica (CNR-INO) and European Laboratory for non Linear Spectroscopy (LENS), via N. Carrara 1, 50019 Sesto Fiorentino, Italy
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3
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Scelta D, Dziubek KF, Ende M, Miletich R, Mezouar M, Garbarino G, Bini R. Extending the Stability Field of Polymeric Carbon Dioxide Phase V beyond the Earth's Geotherm. PHYSICAL REVIEW LETTERS 2021; 126:065701. [PMID: 33635684 DOI: 10.1103/physrevlett.126.065701] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 11/13/2020] [Accepted: 12/11/2020] [Indexed: 06/12/2023]
Abstract
We present a study on the phase stability of dense carbon dioxide (CO_{2}) at extreme pressure-temperature conditions, up to 6200 K within the pressure range 37±9 to 106±17 GPa. The investigations of high-pressure high-temperature in situ x-ray diffraction patterns recorded from laser-heated CO_{2}, as densified in diamond-anvil cells, consistently reproduced the exclusive formation of polymeric tetragonal CO_{2}-V at any condition achieved in repetitive laser-heating cycles. Using well-considered experimental arrangements, which prevent reactions with metal components of the pressure cells, annealing through laser heating was extended individually up to approximately 40 min per cycle in order to keep track of upcoming instabilities and changes with time. The results clearly exclude any decomposition of CO_{2}-V into the elements as previously suggested. Alterations of the Bragg peak distribution on Debye-Scherrer rings indicate grain coarsening at temperatures >4000 K, giving a glimpse of the possible extension of the stability of the polymeric solid phase.
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Affiliation(s)
- Demetrio Scelta
- ICCOM-CNR, Institute of Chemistry of OrganoMetallic Compounds, National Research Council of Italy, Via Madonna del Piano 10, I-50019 Sesto Fiorentino, Firenze, Italy and LENS, European Laboratory for Non-linear Spectroscopy, Via N. Carrara 1, I-50019 Sesto Fiorentino, Firenze, Italy
| | - Kamil F Dziubek
- LENS, European Laboratory for Non-linear Spectroscopy, Via N. Carrara 1, I-50019 Sesto Fiorentino, Firenze, Italy
| | - Martin Ende
- Institut für Mineralogie und Kristallographie, Universität Wien, Althanstrasse 14, A-1090 Wien, Austria
| | - Ronald Miletich
- Institut für Mineralogie und Kristallographie, Universität Wien, Althanstrasse 14, A-1090 Wien, Austria
| | - Mohamed Mezouar
- European Synchrotron Radiation Facility, ESRF, 71 avenue des Martyrs, CS 40220, 38043 Grenoble Cedex 9, France
| | - Gaston Garbarino
- European Synchrotron Radiation Facility, ESRF, 71 avenue des Martyrs, CS 40220, 38043 Grenoble Cedex 9, France
| | - Roberto Bini
- LENS, European Laboratory for Non-linear Spectroscopy, Via N. Carrara 1, I-50019 Sesto Fiorentino, Firenze, Italy; ICCOM-CNR, Institute of Chemistry of OrganoMetallic Compounds, National Research Council of Italy, Via Madonna del Piano 10, I-50019 Sesto Fiorentino, Firenze, Italy; and Dipartimento di Chimica "Ugo Schiff" dell'Università degli Studi di Firenze, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Firenze, Italy
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4
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Zhang H, Tóth O, Liu XD, Bini R, Gregoryanz E, Dalladay-Simpson P, De Panfilis S, Santoro M, Gorelli FA, Martoňák R. Pressure-induced amorphization and existence of molecular and polymeric amorphous forms in dense SO 2. Proc Natl Acad Sci U S A 2020; 117:8736-8742. [PMID: 32245813 PMCID: PMC7183191 DOI: 10.1073/pnas.1917749117] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We report here the pressure-induced amorphization and reversible structural transformation between two amorphous forms of SO2: molecular amorphous and polymeric amorphous, with the transition found at 26 GPa over a broad temperature regime, 77 K to 300 K. The transformation was observed by both Raman spectroscopy and X-ray diffraction in a diamond anvil cell. The results were corroborated by ab initio molecular dynamics simulations, where both forward and reverse transitions were detected, opening a window to detailed analysis of the respective local structures. The high-pressure polymeric amorphous form was found to consist mainly of disordered polymeric chains made of three-coordinated sulfur atoms connected via oxygen atoms, with few residual intact molecules. This study provides an example of polyamorphism in a system consisting of simple molecules with multiple bonds.
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Affiliation(s)
- Huichao Zhang
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China
- University of Science and Technology of China, Hefei 230026, China
| | - Ondrej Tóth
- Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics, Comenius University, 842 48 Bratislava, Slovakia
| | - Xiao-Di Liu
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China;
| | - Roberto Bini
- Department of Chemistry, University of Florence, 50121 Florence, Italy
- European Laboratory for Non-Linear Spectroscopy, 50019 Sesto Fiorentino, Italy
| | - Eugene Gregoryanz
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
- Centre for Science at Extreme Conditions, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
- Center for High Pressure Science Technology Advanced Research, Shanghai, 201203, China
| | | | - Simone De Panfilis
- Centre for Life Nano Science, Istituto Italiano di Tecnologia, 00161 Rome, Italy
| | - Mario Santoro
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China;
- European Laboratory for Non-Linear Spectroscopy, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche (CNR-INO), 50125 Florence, Italy
| | - Federico Aiace Gorelli
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China;
- European Laboratory for Non-Linear Spectroscopy, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche (CNR-INO), 50125 Florence, Italy
| | - Roman Martoňák
- Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics, Comenius University, 842 48 Bratislava, Slovakia;
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5
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Cogollo-Olivo BH, Biswas S, Scandolo S, Montoya JA. Ab initio Determination of the Phase Diagram of CO_{2} at High Pressures and Temperatures. PHYSICAL REVIEW LETTERS 2020; 124:095701. [PMID: 32202852 DOI: 10.1103/physrevlett.124.095701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 02/10/2020] [Indexed: 06/10/2023]
Abstract
The experimental study of the CO_{2} phase diagram is hampered by strong kinetic effects leading to wide regions of metastability and to large uncertainties in the location of some phase boundaries. Here, we determine CO_{2}'s thermodynamic phase boundaries by means of ab initio calculations of the Gibbs free energy of several solid phases of CO_{2} up to 50 Gigapascals. Temperature effects are included in the quasiharmonic approximation. Contrary to previous suggestions, we find that the boundary between molecular forms and the nonmolecular phase V has, indeed, a positive slope and starts at 21.5 GPa at T=0 K. A triple point between phase IV, V, and the liquid phase is found at 35 GPa and 1600 K, indicating a broader region of stability for the nonmolecular form than previously thought. The experimentally determined boundary line between CO_{2}-II and CO_{2}-IV phases is reproduced by our calculations, indicating that kinetic effects do not play a major role in that particular transition. Our results also show that CO_{2}-III is stabilized at high temperature and its stability region coincides with the P-T conditions where phase VII has been reported experimentally; instead, phase II is the most stable molecular phase at low temperatures, extending its region of stability to every P-T condition where phase III is reported experimentally.
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Affiliation(s)
- Beatriz H Cogollo-Olivo
- Universidad de Cartagena, Doctorado en Ciencias Físicas, 130001 Cartagena de Indias, Colombia
| | - Sananda Biswas
- Institut für Theoretische Physik, Goethe-Universität Frankfurt, 60438 Frankfurt am Main, Germany
| | - Sandro Scandolo
- The Abdus Salam International Centre for Theoretical Physics (ICTP), Strada Costiera 11, 34151 Trieste, Italy
| | - Javier A Montoya
- Universidad de Cartagena, Instituto de Matemáticas Aplicadas, 130001 Cartagena de Indias, Colombia
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6
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Nabata H, Takagi M, Saita K, Maeda S. Computational searches for crystal structures of dioxides of group 14 elements (CO 2, SiO 2, GeO 2) under ultrahigh pressure. RSC Adv 2020; 10:22156-22163. [PMID: 35516614 PMCID: PMC9054535 DOI: 10.1039/d0ra03359f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 06/03/2020] [Indexed: 01/20/2023] Open
Abstract
In this study, we focused on the effect of pressure on the crystal structures of dioxides of group 14 elements, i.e. SiO2, GeO2, and CO2.
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Affiliation(s)
- Hitoshi Nabata
- Graduate School of Chemical Sciences and Engineering
- Hokkaido University
- Sapporo 060-8628
- Japan
| | - Makito Takagi
- Graduate School of Nanobioscience
- Yokohama City University
- Yokohama
- Japan
| | - Kenichiro Saita
- Department of Chemistry
- Faculty of Science
- Hokkaido University
- Sapporo 060-0810
- Japan
| | - Satoshi Maeda
- Department of Chemistry
- Faculty of Science
- Hokkaido University
- Sapporo 060-0810
- Japan
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7
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Wu CJ, Young DA, Sterne PA, Myint PC. Equation of state for a chemically dissociative, polyatomic system: Carbon dioxide. J Chem Phys 2019; 151:224505. [PMID: 31837667 DOI: 10.1063/1.5128127] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
A notorious challenge in high-pressure science is to develop an equation of state (EOS) that explicitly treats chemical reactions. For instance, many materials tend to dissociate at high pressures and temperatures where the chemical bonds that hold them together break down. We present an EOS for carbon dioxide (CO2) that allows for dissociation and captures the key material behavior in a wide range of pressure-temperature conditions. Carbon dioxide is an ideal prototype for the development of a wide-ranging EOS that allows for chemical-dissociation equilibria since it is one of the simplest polyatomic systems and because it is of great interest in planetary science and in the study of detonations. Here, we show that taking dissociation into account significantly improves the accuracy of the resulting EOS compared to other EOSs that either neglect chemistry completely or treat CO2 dissociation in a more rudimentary way.
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Affiliation(s)
- Christine J Wu
- Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - David A Young
- Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Philip A Sterne
- Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Philip C Myint
- Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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8
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CO 3+1 network formation in ultra-high pressure carbonate liquids. Sci Rep 2019; 9:15416. [PMID: 31659181 PMCID: PMC6817860 DOI: 10.1038/s41598-019-51306-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 09/24/2019] [Indexed: 11/09/2022] Open
Abstract
Carbonate liquids are an important class of molten salts, not just for industrial applications, but also in geological processes. Carbonates are generally expected to be simple liquids, in terms of ionic interactions between the molecular carbonate anions and metal cations, and therefore relatively structureless compared to more “polymerized” silicate melts. But there is increasing evidence from phase relations, metal solubility, glass spectroscopy and simulations to suggest the emergence of carbonate “networks” at length scales longer than the component molecular anions. The stability of these emergent structures are known to be sensitive to temperature, but are also predicted to be favoured by pressure. This is important as a recent study suggests that subducted surface carbonate may melt near the Earth’s transition zone (~44 km), representing a barrier to the deep carbon cycle depending on the buoyancy and viscosity of these liquids. In this study we demonstrate a major advance in our understanding of carbonate liquids by combining simulations and high pressure measurements on a carbonate glass, (K2CO3-MgCO3) to pressures in excess of 40 GPa, far higher than any previous in situ study. We show the clear formation of extended low-dimensional carbonate networks of close CO32− pairs and the emergence of a “three plus one” local coordination environment, producing an unexpected increase in viscosity with pressure. Although carbonate melts may still be buoyant in the lower mantle, an increased viscosity by at least three orders of magnitude will restrict the upward mobility, possibly resulting in entrainment by the down-going slab.
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9
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10
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Kim M, Ryu YJ, Lim J, Yoo CS. Transformation of molecular CO 2-III in low-density carbon to extended CO 2-V in porous diamond at high pressures and temperatures. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:314002. [PMID: 29957600 DOI: 10.1088/1361-648x/aad02c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The ability to modify chemical bonding in dense heterogeneous solid mixtures by applying high pressure and temperature opens new opportunities to develop a greater number of novel materials with controlled structure, stability and exceptional physical properties. Here, we present the transformation of highly strained CO2-III (Cmca) filled in porous low-density carbons (LDC) to extended CO2-V (I-42d) encapsulated in porous diamond (Fd-3m) at high pressures and temperatures. The x-ray diffraction data indicates the density of porous diamond is about 5%-8% lower than that of bulk diamond and undergoes the structural distortion to monoclinic diamond (C2/m or M-carbon) upon pressure unloading. This result, therefore, demonstrates a feasibility to use porous LDC as nm-scale reactors to synthesize and store carbon dioxide and other high energy density extended solids.
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Affiliation(s)
- Minseob Kim
- Department of Chemistry and Institute for Shock Physics, Washington State University, Pullman, WA 99164, United States of America
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11
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Dziubek KF, Ende M, Scelta D, Bini R, Mezouar M, Garbarino G, Miletich R. Crystalline polymeric carbon dioxide stable at megabar pressures. Nat Commun 2018; 9:3148. [PMID: 30089845 PMCID: PMC6082874 DOI: 10.1038/s41467-018-05593-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 05/11/2018] [Indexed: 11/09/2022] Open
Abstract
Carbon dioxide is a widespread simple molecule in the Universe. In spite of its simplicity it has a very complex phase diagram, forming both amorphous and crystalline extended phases above 40 GPa. The stability range and nature of these phases are still debated, especially in view of their possible role within the deep carbon cycle. Here, we report static synchrotron X-ray diffraction and Raman high-pressure experiments in the megabar range providing evidence for the stability of the polymeric phase V at pressure-temperature conditions relevant to the Earth's lowermost mantle. The equation of state has been extended to 120 GPa and, contrary to earlier experimental findings, neither dissociation into diamond and ε-oxygen nor ionization was observed. Severe deviatoric stress and lattice deformation along with preferred orientation are removed on progressive annealing, thus suggesting CO2-V as the stable structure also above one megabar.
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Affiliation(s)
- Kamil F Dziubek
- LENS, European Laboratory for Non-linear Spectroscopy, Via N. Carrara 1, I-50019, Sesto Fiorentino, Firenze, Italy.
| | - Martin Ende
- Institut für Mineralogie und Kristallographie, Universität Wien, Althanstrasse 14, A-1090, Wien, Austria
| | - Demetrio Scelta
- LENS, European Laboratory for Non-linear Spectroscopy, Via N. Carrara 1, I-50019, Sesto Fiorentino, Firenze, Italy.,ICCOM-CNR, Institute of Chemistry of OrganoMetallic Compounds, National Research Council of Italy, Via Madonna del Piano 10, I-50019, Sesto Fiorentino, Firenze, Italy
| | - Roberto Bini
- LENS, European Laboratory for Non-linear Spectroscopy, Via N. Carrara 1, I-50019, Sesto Fiorentino, Firenze, Italy.,ICCOM-CNR, Institute of Chemistry of OrganoMetallic Compounds, National Research Council of Italy, Via Madonna del Piano 10, I-50019, Sesto Fiorentino, Firenze, Italy.,Dipartimento di Chimica "Ugo Schiff" dell'Università degli Studi di Firenze, Via della Lastruccia 3, I-50019, Sesto Fiorentino, Firenze, Italy
| | - Mohamed Mezouar
- European Synchrotron Radiation Facility, 71 avenue des Martyrs, CS 40220, 38043, Grenoble Cedex 9, France
| | - Gaston Garbarino
- European Synchrotron Radiation Facility, 71 avenue des Martyrs, CS 40220, 38043, Grenoble Cedex 9, France
| | - Ronald Miletich
- Institut für Mineralogie und Kristallographie, Universität Wien, Althanstrasse 14, A-1090, Wien, Austria
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12
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Bai Y, Yu Z, Liu R, Li N, Yan S, Yang K, Liu B, Wei D, Wang L. Pressure-Induced Crystallization and Phase Transformation of Para-xylene. Sci Rep 2017; 7:5321. [PMID: 28706305 PMCID: PMC5509709 DOI: 10.1038/s41598-017-05639-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 06/01/2017] [Indexed: 11/18/2022] Open
Abstract
Static pressure is an alternative method to chemical pressure for tuning the crystal structure, bonds, and physical properties of materials, and is a significant technique for the synthesis of novel materials and fundamental research. In this letter, we report the crystallization and phase transformation of p-xylene under high pressure. Our optical micrographic observations and the appearance of lattice modes in the Raman and infrared (IR) spectra indicated that p-xylene crystallizes at ∼0.1 GPa. The X-ray diffraction (XRD) pattern at 0.84 GPa suggests that the crystallized p-xylene had a monoclinic phase with the Cc(9) space group. The sharp shrinkage of the lattice at ~13 GPa and the solid state of the decompressed sample we observed suggests a new crystalline phase of p-xylene. The in situ XRD showed that the new crystalline phase was still a monoclinic structure but with a different space group of C2(5), indicating that a phase transition occurred during further compression. The mass spectrometry experiment confirmed phase transition polymerization, with mainly trimer and tetramer polymers. Our findings suggest an easy and efficient method for crystallizing and polymerizing p-xylene under high pressure.
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Affiliation(s)
- Yanzhi Bai
- Department of Physics and Astronomy and College of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai, 200240, People's Republic of China.,Center for High Pressure Science and Technology Advanced Research, Shanghai, 201203, People's Republic of China
| | - Zhenhai Yu
- Center for High Pressure Science and Technology Advanced Research, Shanghai, 201203, People's Republic of China
| | - Ran Liu
- State Key Laboratory of Superhard Materials, Jilin University, Changchun, 130012, People's Republic of China
| | - Nana Li
- Center for High Pressure Science and Technology Advanced Research, Shanghai, 201203, People's Republic of China
| | - Shuai Yan
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201203, People's Republic of China
| | - Ke Yang
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201203, People's Republic of China
| | - Bingbing Liu
- State Key Laboratory of Superhard Materials, Jilin University, Changchun, 130012, People's Republic of China
| | - Dongqing Wei
- Department of Physics and Astronomy and College of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai, 200240, People's Republic of China.
| | - Lin Wang
- Center for High Pressure Science and Technology Advanced Research, Shanghai, 201203, People's Republic of China. .,State Key Laboratory of Superhard Materials, Jilin University, Changchun, 130012, People's Republic of China. .,High Pressure Synergetic Consortium, Geophysical Laboratory, Carnegie Institution of Washington, Argonne, Illinois, 60439, United States of America.
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13
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Polymeric phase V of carbon dioxide has not been recovered at ambient pressure and has a unique structure. Proc Natl Acad Sci U S A 2017; 114:E656-E657. [PMID: 28096370 DOI: 10.1073/pnas.1619276114] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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14
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Santamaria-Perez D, McGuire C, Makhluf A, Kavner A, Chuliá-Jordan R, Jorda JL, Rey F, Pellicer-Porres J, Martinez-García D, Rodriguez-Hernández P, Muñoz A. Correspondence: Strongly-driven Re+CO 2 redox reaction at high-pressure and high-temperature. Nat Commun 2016; 7:13647. [PMID: 27897171 PMCID: PMC5141295 DOI: 10.1038/ncomms13647] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- D Santamaria-Perez
- Earth, Planetary and Space Sciences Department, University of California Los Angeles, Los Angeles, California 951567, USA.,MALTA-Departamento de Física Aplicada-ICMUV, Universitat de València, 46100 Valencia, Spain
| | - C McGuire
- Earth, Planetary and Space Sciences Department, University of California Los Angeles, Los Angeles, California 951567, USA
| | - A Makhluf
- Earth, Planetary and Space Sciences Department, University of California Los Angeles, Los Angeles, California 951567, USA
| | - A Kavner
- Earth, Planetary and Space Sciences Department, University of California Los Angeles, Los Angeles, California 951567, USA
| | - R Chuliá-Jordan
- MALTA-Departamento de Física Aplicada-ICMUV, Universitat de València, 46100 Valencia, Spain
| | - J L Jorda
- Instituto de Tecnologia Quimica, Universitat Politècnica de València-CSIC, 46022 Valencia, Spain
| | - F Rey
- Instituto de Tecnologia Quimica, Universitat Politècnica de València-CSIC, 46022 Valencia, Spain
| | - J Pellicer-Porres
- MALTA-Departamento de Física Aplicada-ICMUV, Universitat de València, 46100 Valencia, Spain
| | - D Martinez-García
- MALTA-Departamento de Física Aplicada-ICMUV, Universitat de València, 46100 Valencia, Spain
| | - P Rodriguez-Hernández
- MALTA-Departamento de Física, Instituto Univ. de Materiales y Nanotecnología, Universidad de La Laguna, 38207 La Laguna, Tenerife, Spain
| | - A Muñoz
- MALTA-Departamento de Física, Instituto Univ. de Materiales y Nanotecnología, Universidad de La Laguna, 38207 La Laguna, Tenerife, Spain
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15
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Plašienka D, Martoňák R, Tosatti E. Creating new layered structures at high pressures: SiS 2. Sci Rep 2016; 6:37694. [PMID: 27886243 PMCID: PMC5123579 DOI: 10.1038/srep37694] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 11/03/2016] [Indexed: 12/30/2022] Open
Abstract
Old and novel layered structures are attracting increasing attention for their physical, electronic, and frictional properties. SiS2, isoelectronic to SiO2, CO2 and CS2, is a material whose phases known experimentally up to 6 GPa exhibit 1D chain-like, 2D layered and 3D tetrahedral structures. We present highly predictive ab initio calculations combined with evolutionary structure search and molecular dynamics simulations of the structural and electronic evolution of SiS2 up to 100 GPa. A highly stable CdI2-type layered structure, which is octahedrally coordinated with space group surprisingly appears between 4 and up to at least 100 GPa. The tetrahedral-octahedral switch is naturally expected upon compression, unlike the layered character realized here by edge-sharing SiS6 octahedral units connecting within but not among sheets. The predicted phase is semiconducting with an indirect band gap of about 2 eV at 10 GPa, decreasing under pressure until metallization around 40 GPa. The robustness of the layered phase suggests possible recovery at ambient pressure, where calculated phonon spectra indicate dynamical stability. Even a single monolayer is found to be dynamically stable in isolation, suggesting that it could possibly be sheared or exfoliated from bulk -SiS2.
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Affiliation(s)
- Dušan Plašienka
- Department of Experimental Physics, Comenius University, Mlynská Dolina F2, 842 48 Bratislava, Slovakia
| | - Roman Martoňák
- Department of Experimental Physics, Comenius University, Mlynská Dolina F2, 842 48 Bratislava, Slovakia
| | - Erio Tosatti
- International School for Advanced Studies (SISSA) and CNR-IOM Democritos, Via Bonomea 265, 34136 Trieste, Italy.,The Abdus Salam International Centre for Theoretical Physics (ICTP), Strada Costiera 11, 34151 Trieste, Italy
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16
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Abstract
Structural polymorphism in dense carbon dioxide (CO2) has attracted significant attention in high-pressure physics and chemistry for the past two decades. Here, we have performed high-pressure experiments and first-principles theoretical calculations to investigate the stability, structure, and dynamical properties of dense CO2 We found evidence that CO2-V with the 4-coordinated extended structure can be quenched to ambient pressure below 200 K-the melting temperature of CO2-I. CO2-V is a fully coordinated structure formed from a molecular solid at high pressure and recovered at ambient pressure. Apart from confirming the metastability of CO2-V (I-42d) at ambient pressure at low temperature, results of ab initio molecular dynamics and metadynamics (MD) simulations provided insights into the transformation processes and structural relationship from the molecular to the extended phases. In addition, the simulation also predicted a phase V'(Pna21) in the stability region of CO2-V with a diffraction pattern similar to that previously assigned to the CO2-V (P212121) structure. Both CO2-V and -V' are predicted to be recoverable and hard with a Vicker hardness of ∼20 GPa. Significantly, MD simulations found that the CO2 in phase IV exhibits large-amplitude bending motions at finite temperatures and high pressures. This finding helps to explain the discrepancy between earlier predicted static structures and experiments. MD simulations clearly indicate temperature effects are critical to understanding the high-pressure behaviors of dense CO2 structures-highlighting the significance of chemical kinetics associated with the transformations.
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17
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Qu B, Li D, Wang L, Wu J, Zhou R, Zhang B, Zeng XC. Mechanistic study of pressure and temperature dependent structural changes in reactive formation of silicon carbonate. RSC Adv 2016. [DOI: 10.1039/c5ra21981g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The structure changes of silicon carbonate with pressure and temperature are explored based on systematic ab initio molecular dynamics simulations.
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Affiliation(s)
- Bingyan Qu
- Laboratory of amorphous materials
- School of Materials Science and Engineering
- Hefei University of Technology
- Hefei
- P. R. China
| | - Dongdong Li
- Laboratory of amorphous materials
- School of Materials Science and Engineering
- Hefei University of Technology
- Hefei
- P. R. China
| | - Lei Wang
- Laboratory of amorphous materials
- School of Materials Science and Engineering
- Hefei University of Technology
- Hefei
- P. R. China
| | - Jili Wu
- Laboratory of amorphous materials
- School of Materials Science and Engineering
- Hefei University of Technology
- Hefei
- P. R. China
| | - Rulong Zhou
- Laboratory of amorphous materials
- School of Materials Science and Engineering
- Hefei University of Technology
- Hefei
- P. R. China
| | - Bo Zhang
- Laboratory of amorphous materials
- School of Materials Science and Engineering
- Hefei University of Technology
- Hefei
- P. R. China
| | - Xiao Cheng Zeng
- Department of Chemistry and Nebraska Center for Materials and Nanoscience
- University of Nebraska-Lincoln
- Lincoln
- USA
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18
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Tetrahedrally coordinated carbonates in Earth’s lower mantle. Nat Commun 2015; 6:6311. [DOI: 10.1038/ncomms7311] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Accepted: 01/14/2015] [Indexed: 11/08/2022] Open
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19
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Salamat A, Fischer RA, Briggs R, McMahon MI, Petitgirard S. In situ synchrotron X-ray diffraction in the laser-heated diamond anvil cell: Melting phenomena and synthesis of new materials. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2014.01.034] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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20
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Santoro M, Gorelli FA, Bini R, Salamat A, Garbarino G, Levelut C, Cambon O, Haines J. Carbon enters silica forming a cristobalite-type CO2-SiO2 solid solution. Nat Commun 2014; 5:3761. [PMID: 24781844 PMCID: PMC5603768 DOI: 10.1038/ncomms4761] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 03/31/2014] [Indexed: 11/09/2022] Open
Abstract
Extreme conditions permit unique materials to be synthesized and can significantly update our view of the periodic table. In the case of group IV elements, carbon was always considered to be distinct with respect to its heavier homologues in forming oxides. Here we report the synthesis of a crystalline CO2-SiO2 solid solution by reacting carbon dioxide and silica in a laser-heated diamond anvil cell (P = 16-22 GPa, T>4,000 K), showing that carbon enters silica. Remarkably, this material is recovered to ambient conditions. X-ray diffraction shows that the crystal adopts a densely packed α-cristobalite structure (P4(1)2(1)2) with carbon and silicon in fourfold coordination to oxygen at pressures where silica normally adopts a sixfold coordinated rutile-type stishovite structure. An average formula of C0.6(1)Si0.4(1)O2 is consistent with X-ray diffraction and Raman spectroscopy results. These findings may modify our view on oxide chemistry, which is of great interest for materials science, as well as Earth and planetary sciences.
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Affiliation(s)
- Mario Santoro
- 1] Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche (INO-CNR), Sesto Fiorentino 50019, Italy [2] European Laboratory for Non-Linear Spectroscopy (LENS), Sesto Fiorentino 50019, Italy
| | - Federico A Gorelli
- 1] Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche (INO-CNR), Sesto Fiorentino 50019, Italy [2] European Laboratory for Non-Linear Spectroscopy (LENS), Sesto Fiorentino 50019, Italy
| | - Roberto Bini
- 1] European Laboratory for Non-Linear Spectroscopy (LENS), Sesto Fiorentino 50019, Italy [2] Dipartimento di Chimica dell'Università di Firenze, Sesto Fiorentino 50019, Italy
| | - Ashkan Salamat
- European Synchrotron Radiation Facility, 38043 Grenoble CEDEX 9, France
| | - Gaston Garbarino
- European Synchrotron Radiation Facility, 38043 Grenoble CEDEX 9, France
| | - Claire Levelut
- Laboratoire Charles Coulomb, UMR 5221, Centre National de la Recherche Scientifique (CNRS), Département Colloïdes, Verres et Nanomatériaux (CVN), Université Montpellier 2, 34095 Montpellier CEDEX 5, France
| | - Olivier Cambon
- Institut Charles Gerhardt Montpellier, UMR 5253, Centre National de la Recherche Scientifique (CNRS), Equipe C2M, Université Montpellier 2, 34095 Montpellier CEDEX 5, France
| | - Julien Haines
- Institut Charles Gerhardt Montpellier, UMR 5253, Centre National de la Recherche Scientifique (CNRS), Equipe C2M, Université Montpellier 2, 34095 Montpellier CEDEX 5, France
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21
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Petitgirard S, Salamat A, Beck P, Weck G, Bouvier P. Strategies for in situ laser heating in the diamond anvil cell at an X-ray diffraction beamline. JOURNAL OF SYNCHROTRON RADIATION 2014; 21:89-96. [PMID: 24365921 PMCID: PMC4861204 DOI: 10.1107/s1600577513027434] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 10/06/2013] [Indexed: 05/30/2023]
Abstract
An overview of several innovations regarding in situ laser-heating techniques in the diamond anvil cell at the high-pressure beamline ID27 of the European Synchrotron Radiation Facility is presented. Pyrometry measurements have been adapted to allow simultaneous double-sided temperature measurements with the installation of two additional online laser systems: a CO2 and a pulsed Nd:YAG laser system. This reiteration of laser-heating advancements at ID27 is designed to pave the way for a new generation of state-of-the-art experiments that demand the need for synchrotron diffraction techniques. Experimental examples are provided for each major development. The capabilities of the double pyrometer have been tested with the Nd:YAG continuous-wave lasers but also in a time-resolved configuration using the nanosecond-pulsed Nd:YAG laser on a Fe sample up to 180 GPa and 2900 K. The combination of time-resolved X-ray diffraction with in situ CO2 laser heating is shown with the crystallization of a high-pressure phase of the naturally found pyrite mineral MnS2 (11 GPa, 1100-1650 K).
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Affiliation(s)
- Sylvain Petitgirard
- ID27, European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP 220, 38043 Grenoble Cedex 9, France
- Bayerisches GeoInstitut (BGI), University of Bayreuth, 95444 Bayreuth, Germany
| | - Ashkan Salamat
- ID27, European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP 220, 38043 Grenoble Cedex 9, France
- Lyman Laboratory of Physics, Harvard University, Cambridge, MA 02138, USA
| | - Pierre Beck
- UJF-Grenoble 1/CNRS-INSU, Institut de Planetologie et d’Astrophysique de Grenoble (IPAG), 414 rue de la Piscine, 38000 Grenoble, France
| | - Gunnar Weck
- Commissariat à l’Energie Atomique (CEA), DPTA, 91680 Bruyères le Châtel, France
| | - Pierre Bouvier
- Laboratoire des Materiaux et du Genie Physique, CNRS, Grenoble Institute of Technology, 3 parvis Louis Neel, F-38016 Grenoble, France
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22
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Gohr S, Grimme S, Söhnel T, Paulus B, Schwerdtfeger P. Pressure dependent stability and structure of carbon dioxide—A density functional study including long-range corrections. J Chem Phys 2013; 139:174501. [DOI: 10.1063/1.4826929] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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23
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Abstract
Amorphous silicon oxycarbide polymer-derived ceramics (PDCs), synthesized from organometallic precursors, contain carbon- and silica-rich nanodomains, the latter with extensive substitution of carbon for oxygen, linking Si-centered SiO(x)C(4-x) tetrahedra. Calorimetric studies demonstrated these PDCs to be thermodynamically more stable than a mixture of SiO2, C, and silicon carbide. Here, we show by multinuclear NMR spectroscopy that substitution of C for O is also attained in PDCs with depolymerized silica-rich domains containing lithium, associated with SiO(x)C(4-x) tetrahedra with nonbridging oxygen. We suggest that significant (several percent) substitution of C for O could occur in more complex geological silicate melts/glasses in contact with graphite at moderate pressure and high temperature and may be thermodynamically far more accessible than C for Si substitution. Carbon incorporation will change the local structure and may affect physical properties, such as viscosity. Analogous carbon substitution at grain boundaries, at defect sites, or as equilibrium states in nominally acarbonaceous crystalline silicates, even if present at levels at 10-100 ppm, might form an extensive and hitherto hidden reservoir of carbon in the lower crust and mantle.
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24
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Yoo CS. Physical and chemical transformations of highly compressed carbon dioxide at bond energies. Phys Chem Chem Phys 2013; 15:7949-66. [PMID: 23615853 DOI: 10.1039/c3cp50761k] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Carbon dioxide exhibits a richness of high-pressure polymorphs with a great diversity in intermolecular interaction, chemical bonding, and crystal structures. It ranges from typical molecular solids to fully extended covalent solids with crystal structures similar to those of SiO2. These extended solids of carbon dioxide are fundamentally new materials exhibiting interesting optical nonlinearity, low compressibility and high energy density. Furthermore, the large disparity in chemical bonding between the extended network and molecular structures results in a broad metastability domain for these phases to room temperature and almost to ambient pressure and thereby offers enhanced opportunities for novel materials developments. Broadly speaking, these molecular-to-non-molecular transitions occur due to electron delocalization manifested as a rapid increase in electron kinetic energy at high density. The detailed mechanisms, however, are more complex with phase metastabilities, path-dependent phases and phase boundaries, and large lattice strains and structural distortions - all of which are controlled by well beyond thermodynamic constraints to chemical kinetics associated with the governing phases and transitions. As a result, the equilibrium phase boundary is difficult to locate precisely (experimentally or theoretically) and is often obscured by the presence of metastable phases (ordered or disordered). This paper will review the pressure-induced transformations observed in highly compressed carbon dioxide and present chemistry perspectives on those molecular-to-non-molecular transformations that can be applied to other low-Z molecular solids at Mbar pressures where the compression energy rivals the chemical bond energies.
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Affiliation(s)
- Choong-Shik Yoo
- Department of Chemistry and Institute of Shock Physics, Washington State University, Pullman, Washington 99164, USA.
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25
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Morales-García A, Marqués M, Menéndez JM, Santamaría-Pérez D, Baonza VG, Recio JM. First-principles study of structure and stability in Si–C–O-based materials. Theor Chem Acc 2012. [DOI: 10.1007/s00214-012-1308-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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26
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Abstract
We present ab initio calculations of the phase diagram of liquid CO(2) and its melting curve over a wide range of pressure and temperature conditions, including those relevant to the Earth. Several distinct liquid phases are predicted up to 200 GPa and 10,000 K based on their structural and electronic characteristics. We provide evidence for a first-order liquid-liquid phase transition with a critical point near 48 GPa and 3,200 K that intersects the mantle geotherm; a liquid-liquid-solid triple point is predicted near 45 GPa and 1,850 K. Unlike known first-order transitions between thermodynamically stable liquids, the coexistence of molecular and polymeric CO(2) phases predicted here is not accompanied by metallization. The absence of an electrical anomaly would be unique among known liquid-liquid transitions. Furthermore, the previously suggested phase separation of CO(2) into its constituent elements at lower mantle conditions is examined by evaluating their Gibbs free energies. We find that liquid CO(2) does not decompose into carbon and oxygen up to at least 200 GPa and 10,000 K.
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Affiliation(s)
- Brian Boates
- Lawrence Livermore National Laboratory, Livermore, CA 94550; and
- Department of Physics, Dalhousie University, Halifax, NS, Canada B3H 3J5
| | | | - Stanimir A. Bonev
- Lawrence Livermore National Laboratory, Livermore, CA 94550; and
- Department of Physics, Dalhousie University, Halifax, NS, Canada B3H 3J5
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27
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Ledyastuti M, Liang Y, Miranda CR, Matsuoka T. Comparison of thermodynamic stabilities and mechanical properties of CO2, SiO2, and GeO2 polymorphs by first-principles calculations. J Chem Phys 2012; 137:034703. [DOI: 10.1063/1.4735077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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