1
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Zhao Y, You J, Wang J, Wang M, Tang K, Lu L, Zhang Q, Wan S, Gong X, Liu G. Quantitative Studies on Local Structure of Molten Binary Potassium Germanates. Inorg Chem 2023. [PMID: 37402319 DOI: 10.1021/acs.inorgchem.2c04310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/06/2023]
Abstract
In situ high temperature Raman spectra of xK2O-(100-x)GeO2, samples containing 0, 5, 11.11, 20, 25, 33.3, 40, and 50 %mol K2O, were measured. The structure units and a series of model clusters have been designed, optimized, and calculated by quantum chemistry ab initio calculations. The computational simulation in conjunction with the experiments put forward a novel method to correct the experimental Raman spectra of the melts. Deconvolution of the stretching vibrational bands of nonbridging oxygen of [GeO4] tetrahedra of Raman spectra by Gaussian functions was carried out, and the quantitative distribution of different Qn species in molten binary potassium germanates was obtained. The result on all molten samples show that four-fold coordinated germanium atoms occupy a dominant position in the melt and only four-fold coordinated exists in the melt when the K2O content exceeds a certain amount. For melts with high GeO2 content, with the increasing K2O content, the structure of [GeO4] tetrahedra gradually changes from a three-dimensional network consisting of both six-membered and three-membered rings to a three-dimensional network that presents all three-membered rings.
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Affiliation(s)
- Yufan Zhao
- State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
| | - Jinglin You
- State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
| | - Jian Wang
- State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
| | - Min Wang
- State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
| | - Kai Tang
- SINTEF Industry, Trondheim 7094, Norway
| | - Liming Lu
- Technology Court, Pullenvale, CSIRO Mineral Resources, Queensland 4069, Australia
| | - Qingli Zhang
- Anhui Key Laboratory for Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China
| | - Songming Wan
- Anhui Key Laboratory for Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China
| | - Xiaoye Gong
- State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
| | - Guopeng Liu
- State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
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Benmore CJ, González GB, Alderman OLG, Wilke SK, Yarger JL, Leinenweber K, Weber JKR. Hard x-ray methods for studying the structure of amorphous thin films and bulk glassy oxides. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:194001. [PMID: 33540391 DOI: 10.1088/1361-648x/abe352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Accepted: 02/04/2021] [Indexed: 06/12/2023]
Abstract
High-energy photon diffraction minimizes many of the corrections associated with laboratory x-ray diffractometers, and enables structure factor measurements to be made over a wide range of momentum transfers. The method edges us closer toward an ideal experiment, in which coordination numbers can be extracted without knowledge of the sample density. Three case studies are presented that demonstrate new hard x-ray methods for studying the structure of glassy and amorphous materials. First, the methodology and analysis of high-energy grazing incidence on thin films is discussed for the case of amorphous In2O3. The connectivity of irregular InO6polyhedra are shown to exist in face-, edge- and corner-shared configurations in the approximate ratio of 1:2:3. Secondly, the technique of high-energy small and wide angle scattering has been carried out on laser heated and aerodynamically levitated samples of silica-rich barium silicate (20BaO:80SiO2), from the single phase melt at 1500oC to the phase separated glass at room temperature. Based on Ba-O coordination numbers of 6 to 7, it is argued that the although the potential of Ba is ionic, it is weak enough to cause the liquid-liquid immiscibility to become metastable. Lastly, high-energy small and wide angle scattering has also been applied to high water content (up to 12 wt.%) samples of hydrous SiO2glass quenched from 1500oC at 4 GPa. An increase of Si1-O2correlations at 4.3 Å is found to be consistent with an increase in the population of three-membered SiO4rings at the expense of larger rings.
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Affiliation(s)
- C J Benmore
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, United States of America
- Arizona State University, Tempe, AZ 85287, United States of America
| | - G B González
- Department of Physics, DePaul University, Chicago, Illinois 60614, United States of America
| | - O L G Alderman
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Campus, Didcot OX11 0QX, United Kingdom
| | - S K Wilke
- Materials Development, Inc., Evanston, IL 60202, United States of America
| | - J L Yarger
- Arizona State University, Tempe, AZ 85287, United States of America
| | - K Leinenweber
- Arizona State University, Tempe, AZ 85287, United States of America
| | - J K R Weber
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, United States of America
- Materials Development, Inc., Evanston, IL 60202, United States of America
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Lee SK, Mun KY, Kim YH, Lhee J, Okuchi T, Lin JF. Degree of Permanent Densification in Oxide Glasses upon Extreme Compression up to 24 GPa at Room Temperature. J Phys Chem Lett 2020; 11:2917-2924. [PMID: 32223166 DOI: 10.1021/acs.jpclett.0c00709] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
During the decompression of plastically deformed glasses at room temperature, some aspects of irreversible densification may be preserved. This densification has been primarily attributed to topological changes in glass networks. The changes in short-range structures like cation coordination numbers are often assumed to be relaxed upon decompression. Here the NMR results for aluminosilicate glass upon permanent densification up to 24 GPa reveal noticeable changes in the Al coordination number under pressure conditions as low as ∼6 GPa. A drastic increase in the highly coordinated Al fraction is evident over only a relatively narrow pressure range of up to ∼12 GPa, above which the coordination change becomes negligible up to 24 GPa. In contrast, Si coordination environments do not change, highlighting preferential coordination transformation during deformation. The observed trend in the coordination environment shows a remarkable similarity to the pressure-induced changes in the residual glass density, yielding a predictive relationship between the irreversible densification and the detailed structures under extreme compression. The results open a way to access the nature of plastic deformation in complex glasses at room temperature.
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Affiliation(s)
- Sung Keun Lee
- Laboratory of Physics and Chemistry of Earth Materials, School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Korea
- Institute of Applied Physics, Seoul National University, Seoul 08826, Korea
| | - Kwan Young Mun
- Laboratory of Physics and Chemistry of Earth Materials, School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Korea
| | - Yong-Hyun Kim
- Laboratory of Physics and Chemistry of Earth Materials, School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Korea
| | - Juho Lhee
- Laboratory of Physics and Chemistry of Earth Materials, School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Korea
| | - Takuo Okuchi
- Institute for Planetary Materials, Okayama University, Misasa 682-0193, Japan
| | - Jung-Fu Lin
- Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas 78712, United States
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Johari GP. Increasing the Ambient Pressure Solubility by Forming a Glass at High Pressure and Its Thermodynamics, a Much Sought-After Pharmaceutical Advantage. J Phys Chem B 2018; 122:2031-2039. [DOI: 10.1021/acs.jpcb.7b12432] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- G. P. Johari
- Department of Materials Science and
Engineering, McMaster University, Hamilton, Ontario L8S 4L7, Canada
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5
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Mantisi B, Kermouche G, Barthel E, Tanguy A. Impact of pressure on plastic yield in amorphous solids with open structure. Phys Rev E 2016; 93:033001. [PMID: 27078435 DOI: 10.1103/physreve.93.033001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Indexed: 11/07/2022]
Abstract
Plasticity in amorphous silica is unusual: The yield stress decreases with hydrostatic pressure, in contrast to the Mohr-Coulomb response commonly found in more compact materials such as bulk metallic glasses. To better understand this response, we have carried out molecular dynamics simulations of plastic response in a model glass with open structure. The simulations reproduce the anomalous dependence of yield stress with pressure and also correctly predict that the plastic response turns to normal once the material has been fully compacted. We also show that the overall shape of the yield surface is consistent with a quadratic behavior predicted assuming local buckling of the structure, a point of view that fits well into the present understanding of the deformation mechanisms of amorphous silica. The results also confirm that free volume is an adequate internal variable for a continuum scale description of the plastic response of amorphous silica. Finally, we also investigate the long-range correlations between rearrangement events. We find that strong intermittency is observed when the structure remains open, while compaction results in more homogeneous rearrangements. These findings are in agreement with recent results on the effect of compression on the middle range order in silicate glasses and also suggest that the well-known volume recovery of densified silica at relatively low temperatures is in fact a form of aging.
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Affiliation(s)
- B Mantisi
- Laboratoire de Physique Théorique de la Matière Condensée, Paris Sorbonne Universités UPMC, BP 121, 4 Place Jussieu, 75252 Paris Cedex 05, France
| | - G Kermouche
- Materials Sciences and Structures Division, Ecole des Mines de Saint-Etienne, LGF UMR No. 5307, CNRS, 158 Cours Fauriel, 42023 Saint-Etienne Cedex 2, France
| | - E Barthel
- École Supérieure de Physique et de Chimie Industrielles de la Ville de Paris ParisTech, PSL Research University, Sciences et Ingénierie de la matière Molle, CNRS UMR No. 7615, 10 Rue Vauquelin, F-75231 Paris Cedex 05, France and Sorbonne-Universités, UPMC Université Paris 06, SIMM, 10 Rue Vauquelin, 75231 Paris Cedex 05, France
| | - A Tanguy
- Université de Lyon, LaMCoS, INSA-Lyon, CNRS UMR5259, F-69621, France
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6
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Smedskjaer MM, Bauchy M, Mauro JC, Rzoska SJ, Bockowski M. Unique effects of thermal and pressure histories on glass hardness: Structural and topological origin. J Chem Phys 2015; 143:164505. [DOI: 10.1063/1.4934540] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Affiliation(s)
- Morten M. Smedskjaer
- Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Mathieu Bauchy
- Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095, USA
| | - John C. Mauro
- Science and Technology Division, Corning Incorporated, Corning, New York 14831, USA
| | - Sylwester J. Rzoska
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw 01-142, Poland
- Institute of Physics, University of Silesia, Chorzow 41-500, Poland
| | - Michal Bockowski
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw 01-142, Poland
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7
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Zanatta M, Baldi G, Brusa RS, Egger W, Fontana A, Gilioli E, Mariazzi S, Monaco G, Ravelli L, Sacchetti F. Structural evolution and medium range order in permanently densified vitreous SiO2. PHYSICAL REVIEW LETTERS 2014; 112:045501. [PMID: 24580465 DOI: 10.1103/physrevlett.112.045501] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Indexed: 06/03/2023]
Abstract
Positron annihilation lifetime spectroscopy is employed to measure the size of the interstitial void spaces characterizing the structure of a set of permanently densified SiO2 glasses. The average volume of the voids is markedly affected by the densification process and linearly shrinks by almost an order of magnitude after a relative density variation of 22%. In addition, x-ray diffraction shows that this change of density does not modify appreciably the short range order, which remains organized in SiO4 tetrahedra. These results strongly suggest a porous medium description for v-SiO2 glasses where the compressibility and the medium range order are dominated by the density variation of the voids volume up to densities close to that of α-quartz.
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Affiliation(s)
- M Zanatta
- Dipartimento di Fisica, Università di Perugia, I-06123 Perugia, Italy
| | - G Baldi
- IMEM-CNR, I-43124 Parma, Italy
| | - R S Brusa
- Dipartimento di Fisica, Università di Trento, I-38123 Povo, Trento, Italy
| | - W Egger
- Institut für Angewandte Physik und Messtechnik, Universität der Bundeswehr München, D-85577 Neubiberg, Germany
| | - A Fontana
- Dipartimento di Fisica, Università di Trento, I-38123 Povo, Trento, Italy
| | | | - S Mariazzi
- Dipartimento di Fisica, Università di Trento, I-38123 Povo, Trento, Italy
| | - G Monaco
- Dipartimento di Fisica, Università di Trento, I-38123 Povo, Trento, Italy
| | - L Ravelli
- Institut für Angewandte Physik und Messtechnik, Universität der Bundeswehr München, D-85577 Neubiberg, Germany
| | - F Sacchetti
- Dipartimento di Fisica, Università di Perugia, I-06123 Perugia, Italy and IOM-CNR c/o Dipartimento di Fisica, Università di Perugia, I-06123 Perugia, Italy
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8
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Wang Y, Sakamaki T, Skinner LB, Jing Z, Yu T, Kono Y, Park C, Shen G, Rivers ML, Sutton SR. Atomistic insight into viscosity and density of silicate melts under pressure. Nat Commun 2014; 5:3241. [DOI: 10.1038/ncomms4241] [Citation(s) in RCA: 107] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 01/10/2014] [Indexed: 11/10/2022] Open
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9
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Salmon PS, Zeidler A. Identifying and characterising the different structural length scales in liquids and glasses: an experimental approach. Phys Chem Chem Phys 2013; 15:15286-308. [DOI: 10.1039/c3cp51741a] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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10
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Wezka K, Salmon PS, Zeidler A, Whittaker DAJ, Drewitt JWE, Klotz S, Fischer HE, Marrocchelli D. Mechanisms of network collapse in GeO2 glass: high-pressure neutron diffraction with isotope substitution as arbitrator of competing models. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:502101. [PMID: 23164808 DOI: 10.1088/0953-8984/24/50/502101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The structure of the network forming glass GeO(2) is investigated by making the first application of the method of in situ neutron diffraction with isotope substitution at pressures increasing from ambient to 8 GPa. Of the various models, the experimental results are in quantitative agreement only with molecular dynamics simulations made using interaction potentials that include dipole-polarization effects. When the reduced density ρ/ρ(0) > or approximately equal to 1.16, where ρ(0) is the value at ambient pressure, network collapse proceeds via an interplay between the predominance of distorted square pyramidal GeO(5) units versus octahedral GeO(6) units as they replace tetrahedral GeO(4) units. This replacement necessitates the formation of threefold coordinated oxygen atoms and leads to an increase with density in the number of small rings, where a preference is shown for sixfold rings when ρ/ρ(0) = 1 and fourfold rings when ρ/ρ(0) = 1.64.
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Affiliation(s)
- Kamil Wezka
- Department of Physics, University of Bath, Bath, UK
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11
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Johnson JA, Benmore CJ, Holland D, Du J, Beuneu B, Mekki A. Influence of rare-earth ions on SiO₂-Na₂O-RE₂O₃ glass structure. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2011; 23:065404. [PMID: 21406929 DOI: 10.1088/0953-8984/23/6/065404] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Praseodymium and europium sodium silicate glasses of nominal composition (SiO(2))(0.70 - x)(Na(2)O)(0.30)(RE(2)O(3))(x), where RE is the rare earth and 0 ≤ x ≤ 0.10, were studied by neutron and high-energy x-ray scattering and classical molecular dynamics simulations. The observation of a significant x-ray intensity in doped as compared to un-doped glasses is indicative of RE-RE correlations at a distance of ∼ 3.7-3.9 Å, much shorter than would be expected for a homogeneous distribution, suggesting that clustering of the rare-earth cations occurs in both these glass systems at low concentrations. Above x = 0.075 (nominal), minimal changes in this region indicate that the RE atoms are incorporated much more randomly into the glass structure. The molecular dynamics simulations suggest that the rare-earth ions enter the sodium-rich regions in the sodium silicate glasses and act as modifiers. A cluster analysis performed on the model systems indicates that the tendency for clustering is higher in praseodymium-containing glasses than in the europium glasses.
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Affiliation(s)
- J A Johnson
- Department of Materials Science and Engineering, University of Tennessee Space Institute, Tullahoma, TN 37388, USA.
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Brazhkin VV, Akola J, Katayama Y, Kohara S, Kondrin MV, Lyapin AG, Lyapin SG, Tricot G, Yagafarov OF. Densified low-hygroscopic form of P2O5 glass. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm10889a] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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13
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Wang L, Li J, Fecht HJ. Single-exponential activation behavior behind the super-Arrhenius relaxations in glass-forming liquids. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:455104. [PMID: 21339624 DOI: 10.1088/0953-8984/22/45/455104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The reported relaxation time for several typical glass-forming liquids was analyzed by using a kinetic model for liquids which invoked a new kind of atomic cooperativity--thermodynamic cooperativity. The broadly studied 'cooperative length' was recognized as the kinetic cooperativity. Both cooperativities were conveniently quantified from the measured relaxation data. A single-exponential activation behavior was uncovered behind the super-Arrhenius relaxations for the liquids investigated. Hence the mesostructure of these liquids and the atomic mechanism of the glass transition became clearer.
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Affiliation(s)
- Lianwen Wang
- Institute of Materials Science and Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China.
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14
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Soper AK. Network structure and concentration fluctuations in a series of elemental, binary, and tertiary liquids and glasses. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:404210. [PMID: 21386571 DOI: 10.1088/0953-8984/22/40/404210] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Liquids and glasses continue to produce a lively debate about the nature of the disordered structure in these materials, and whether it is driven by longer range concentration or density fluctuations. One factor often lacking in these studies is an overview of a wide range of structures from which common features of and differences between materials can be identified. Here I examine the structure of a wide range of chain and network, elemental, binary and tertiary liquids and glasses, using available x-ray and neutron diffraction data and combining them with empirical potential structure refinement. Calculation of the Bhatia-Thornton number-number and concentration-concentration structure factors and distribution functions highlights common structural motifs that run through many of the series. It is found that the greatest structural overlap occurs where the nearest-neighbour and second-neighbour coordination numbers are similar for different materials. As these coordination numbers increase, so the structures undergo a sequence of characteristic changes involving increasingly bent bond angle distributions and increased packing fractions. In these regards liquid and amorphous phosphorus appear to be in a structural class of their own, combining both chain-like and network-like characteristics.
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Affiliation(s)
- Alan K Soper
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon OX11 0QX, UK.
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15
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D’Angelo G, Crupi C, González MÁ, Basile E, Conti Nibali V, Mondelli C. Prepeak and First Sharp Diffraction Peak in the Structure Factor of (Cs2O)0.14(B2O3)0.86 Glass: Influence of Temperature. J Phys Chem B 2010; 114:12565-71. [DOI: 10.1021/jp1005555] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Giovanna D’Angelo
- Dipartimento di Fisica, University of Messina, Salita Sperone 31, Villaggio S. Agata, 98166 Messina, Italy, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France, Scuola di Specializzazione in Fisica Sanitaria, Università degli Studi ‘La Sapienza’, Roma, Italy, Dipartimento Tecnologie e Salute, Istituto Superiore di Sanità, Roma, Italy, and CNR-INFM OGG, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France
| | - Cristina Crupi
- Dipartimento di Fisica, University of Messina, Salita Sperone 31, Villaggio S. Agata, 98166 Messina, Italy, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France, Scuola di Specializzazione in Fisica Sanitaria, Università degli Studi ‘La Sapienza’, Roma, Italy, Dipartimento Tecnologie e Salute, Istituto Superiore di Sanità, Roma, Italy, and CNR-INFM OGG, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France
| | - Miguel Ángel González
- Dipartimento di Fisica, University of Messina, Salita Sperone 31, Villaggio S. Agata, 98166 Messina, Italy, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France, Scuola di Specializzazione in Fisica Sanitaria, Università degli Studi ‘La Sapienza’, Roma, Italy, Dipartimento Tecnologie e Salute, Istituto Superiore di Sanità, Roma, Italy, and CNR-INFM OGG, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France
| | - Emilia Basile
- Dipartimento di Fisica, University of Messina, Salita Sperone 31, Villaggio S. Agata, 98166 Messina, Italy, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France, Scuola di Specializzazione in Fisica Sanitaria, Università degli Studi ‘La Sapienza’, Roma, Italy, Dipartimento Tecnologie e Salute, Istituto Superiore di Sanità, Roma, Italy, and CNR-INFM OGG, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France
| | - Valeria Conti Nibali
- Dipartimento di Fisica, University of Messina, Salita Sperone 31, Villaggio S. Agata, 98166 Messina, Italy, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France, Scuola di Specializzazione in Fisica Sanitaria, Università degli Studi ‘La Sapienza’, Roma, Italy, Dipartimento Tecnologie e Salute, Istituto Superiore di Sanità, Roma, Italy, and CNR-INFM OGG, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France
| | - Claudia Mondelli
- Dipartimento di Fisica, University of Messina, Salita Sperone 31, Villaggio S. Agata, 98166 Messina, Italy, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France, Scuola di Specializzazione in Fisica Sanitaria, Università degli Studi ‘La Sapienza’, Roma, Italy, Dipartimento Tecnologie e Salute, Istituto Superiore di Sanità, Roma, Italy, and CNR-INFM OGG, Institute Laue Langevin 6, Rue Jules Horowitz, 38042 Grenoble, France
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16
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Wurden C, Page K, Llobet A, White CE, Proffen T. Extracting differential pair distribution functions usingMIXSCAT. J Appl Crystallogr 2010. [DOI: 10.1107/s0021889810009155] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Differently weighted experimental scattering data have been used to extract partial or differential structure factors or pair distribution functions in studying many materials. However, this is not done routinely partly because of the lack of user-friendly software. This paper presentsMIXSCAT, a new member of theDISCUSprogram package.MIXSCATallows one to combine neutron and X-ray pair distribution functions and extract their respective differential functions.
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17
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Kibalchenko M, Yates JR, Pasquarello A. First-principles investigation of the relation between structural and NMR parameters in vitreous GeO2. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:145501. [PMID: 21389530 DOI: 10.1088/0953-8984/22/14/145501] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
NMR parameters of (73)Ge and (17)O in vitreous GeO(2) and quartz GeO(2), including the isotropic shifts, the quadrupole coupling constants C(Q), and the electric-field-gradient asymmetry parameters η, are determined through density functional calculations. Clear correlations are established between (73)Ge shifts and the mean of the four neighboring Ge-O-Ge bond angles, and between C(Q) and η parameters of (17)O and the local Ge-O-Ge angle. Available experimental data for C(Q) and the corresponding established correlation are used to extract the value of 135° for the average Ge-O-Ge angle in vitreous GeO(2). The features of the Ge-O-Ge bond angle distribution of vitreous GeO(2) derived in this work are consistent with those inferred from other experimental probes.
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Affiliation(s)
- Mikhail Kibalchenko
- TCM Group, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK.
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Orsingher L, Fontana A, Gilioli E, Carini G, Carini G, Tripodo G, Unruh T, Buchenau U. Vibrational dynamics of permanently densified GeO2 glasses: Densification-induced changes in the boson peak. J Chem Phys 2010; 132:124508. [DOI: 10.1063/1.3360039] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Le Parc R, Ranieri V, Haines J, Cambon M, Cambon O, Levelut C, Clément S. In situ high pressure and high temperature Raman studies of (1-x)SiO(2)xGeO(2) glasses. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:375109. [PMID: 21832340 DOI: 10.1088/0953-8984/21/37/375109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The structure of glasses in the binary system SiO(2)-GeO(2) has been studied by Raman spectroscopy. Our results are consistent with mixing of SiO(2) and GeO(2) tetrahedra. The changes induced by temperature and by pressure on the structure are monitored by in situ measurements on the same mixed glasses. Anomalous temperature dependences are observed not only for SiO(2) glass and GeO(2) glass but also for mixed glasses. Particular attention is focused on the pressure densification mechanism in mixed glasses. Via the pressure dependence of the width of the main Raman band, we show that the compression mechanism in mixed glasses is intermediate between that of the end members.
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Affiliation(s)
- R Le Parc
- Laboratoire des Colloides Verres et Nanomatériaux, UMR CNRS-UM2 5587, Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France
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20
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Loerting T, Brazhkin VV, Morishita T. Multiple Amorphous-Amorphous Transitions. ADVANCES IN CHEMICAL PHYSICS 2009. [DOI: 10.1002/9780470508602.ch2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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21
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Vaccari M, Aquilanti G, Pascarelli S, Mathon O. A new EXAFS investigation of local structural changes in amorphous and crystalline GeO(2) at high pressure. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:145403. [PMID: 21825334 DOI: 10.1088/0953-8984/21/14/145403] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Structural transformations at high pressure in amorphous and quartz-like crystalline GeO(2) have been investigated by using a Paris-Edinburgh press coupled to EXAFS spectroscopy. From both the germanium absorption edge position and the Ge-O distance evolution, new detailed information has been obtained about the pressure behavior of the short range order. Crystalline GeO(2) undergoes a transformation from four- to six-fold coordination at about 8.5 GPa, but at least the whole 6-12 GPa pressure range should be considered as the transition region. On the other hand, amorphous GeO(2) is characterized by a much more gradual structural change and the full octahedral state is not reached at 13 GPa as commonly believed. Furthermore, no support to the recently claimed fully pentahedral intermediate state can be given. EXAFS signals of glassy GeO(2) beyond the first Ge-O shell qualitatively confirm the continuous breakdown of the intermediate range order up to 10 GPa.
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Affiliation(s)
- M Vaccari
- European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP 220, 38043 Grenoble Cedex, France
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22
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Weber R, Sen S, Youngman RE, Hart RT, Benmore CJ. Structure of High Alumina Content Al2O3−SiO2 Composition Glasses. J Phys Chem B 2008; 112:16726-33. [DOI: 10.1021/jp807964u] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Richard Weber
- Materials Development, Inc., Arlington Heights, Illinois 60004, Department of Chemical Engineering and Materials Science, University of California-Davis, Davis, California 95616, Corning, Inc., Corning, New York 14831, Shepherd Chemical Company, Norwood, Ohio 45212, and Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439
| | - Sabyasachi Sen
- Materials Development, Inc., Arlington Heights, Illinois 60004, Department of Chemical Engineering and Materials Science, University of California-Davis, Davis, California 95616, Corning, Inc., Corning, New York 14831, Shepherd Chemical Company, Norwood, Ohio 45212, and Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439
| | - Randall E. Youngman
- Materials Development, Inc., Arlington Heights, Illinois 60004, Department of Chemical Engineering and Materials Science, University of California-Davis, Davis, California 95616, Corning, Inc., Corning, New York 14831, Shepherd Chemical Company, Norwood, Ohio 45212, and Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439
| | - Robert T. Hart
- Materials Development, Inc., Arlington Heights, Illinois 60004, Department of Chemical Engineering and Materials Science, University of California-Davis, Davis, California 95616, Corning, Inc., Corning, New York 14831, Shepherd Chemical Company, Norwood, Ohio 45212, and Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439
| | - Chris J. Benmore
- Materials Development, Inc., Arlington Heights, Illinois 60004, Department of Chemical Engineering and Materials Science, University of California-Davis, Davis, California 95616, Corning, Inc., Corning, New York 14831, Shepherd Chemical Company, Norwood, Ohio 45212, and Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439
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23
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Giacomazzi L, Pasquarello A. Vibrational spectra of vitreous SiO 2 and vitreous GeO 2 from first principles. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2007; 19:415112. [PMID: 28192324 DOI: 10.1088/0953-8984/19/41/415112] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Using a density-functional approach, we calculate the principal vibrational spectra of vitreous SiO2 and vitreous GeO2 and discuss their analogies and differences. For both glasses, we generate model structures consisting of a random network of corner-sharing tetrahedra and differing only by their packing density. The comparison between calculated and measured neutron structure factors supports the validity of our model structures. Our investigation then extends to the vibrational properties, including the inelastic-neutron, infrared, and Raman spectra. For these spectra, good agreement with experiment is also found. Our results support the picture that silica and germania are constituted by a continuous random network of corner-sharing tetrahedra. In particular, the good agreement with experiment for the Raman spectra supports the average intertetrahedral angles of 148° and 135° found in our models of vitreous SiO2 and vitreous GeO2, respectively. The concentration of small ring structures in these glasses is also discussed.
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24
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Salmon PS, Barnes AC, Martin RA, Cuello GJ. Structure of glassy GeO 2. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2007; 19:415110. [PMID: 28192322 DOI: 10.1088/0953-8984/19/41/415110] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The full set of partial structure factors for glassy germania, or GeO2, were accurately measured by using the method of isotopic substitution in neutron diffraction in order to elucidate the nature of the pair correlations for this archetypal strong glass former. The results show that the basic tetrahedral Ge(O1/2)4 building blocks share corners with a mean inter-tetrahedral Ge-Ô-Ge bond angle of 132(2)°. The topological and chemical ordering in the resultant network displays two characteristic length scales at distances greater than the nearest neighbour. One of these describes the intermediate range order, and manifests itself by the appearance of a first sharp diffraction peak in the measured diffraction patterns at a scattering vector kFSDP≈1.53 Å-1, while the other describes so-called extended range order, and is associated with the principal peak at kPP = 2.66(1) Å-1. We find that there is an interplay between the relative importance of the ordering on these length scales for tetrahedral network forming glasses that is dominated by the extended range ordering with increasing glass fragility. The measured partial structure factors for glassy GeO2 are used to reproduce the total structure factor measured by using high energy x-ray diffraction and the experimental results are also compared to those obtained by using classical and first principles molecular dynamics simulations.
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25
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Shen G, Liermann HP, Sinogeikin S, Yang W, Hong X, Yoo CS, Cynn H. Distinct thermal behavior of GeO2 glass in tetrahedral, intermediate, and octahedral forms. Proc Natl Acad Sci U S A 2007; 104:14576-9. [PMID: 17804799 PMCID: PMC1976207 DOI: 10.1073/pnas.0703098104] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2007] [Indexed: 11/18/2022] Open
Abstract
One fascinating high-pressure behavior of tetrahedral glasses and melts is the local coordination change with increasing pressure, which provides a structural basis for understanding numerous anomalies in their high-pressure properties. Because the coordination change is often not retained upon decompression, studies must be conducted in situ. Previous in situ studies have revealed that the short-range order of tetrahedrally structured glasses and melts changes above a threshold pressure and gradually transforms to an octahedral form with further pressure increase. Here, we report a thermal effect associated with the coordination change at given pressures and show distinct thermal behaviors of GeO(2) glass in tetrahedral, octahedral, and their intermediate forms. An unusual thermally induced densification, as large as 16%, was observed on a GeO(2) glass at a pressure of 5.5 gigapascal (GPa), based on in situ density and x-ray diffraction measurements at simultaneously high pressures and high temperatures. The large thermal densification at high pressure was found to be associated with the 4- to 6-fold coordination increase. Experiments at other pressures show that the tetrahedral GeO(2) glass displayed small thermal densification at 3.3 GPa arising from the relaxation of intermediate range structure, whereas the octahedral glass at 12.3 GPa did not display any detectable thermal effects.
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Affiliation(s)
- Guoyin Shen
- High Pressure Collaborative Access Team, Geophysical Laboratory, Carnegie Institution of Washington, Argonne, IL 60439, USA.
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26
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Sefzik TH, Clark TM, Grandinetti PJ. A computational investigation of 17O quadrupolar coupling parameters and structure in alpha-quartz phase GeO2. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2007; 32:16-23. [PMID: 17686616 DOI: 10.1016/j.ssnmr.2007.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Revised: 06/04/2007] [Indexed: 05/16/2023]
Abstract
Ab initio band-structure calculations based on density functional theory have been completed for alpha-quartz phase GeO2 to obtain electric-field gradients (efg) for oxygen atoms, including those for GeO2 at elevated pressure and temperature. To interpret the resulting efg values and examine correlations between structure and 17O quadrupolar coupling parameters, additional ab initio self-consistent Hartree-Fock molecular orbital calculations were completed. The quadrupolar coupling constant was found to have a strong dependence on Ge-O distance and angleGe-O-Ge, with the quadrupolar asymmetry parameter being primarily dependent on angleGe-O-Ge. Analytical expressions describing these dependencies consistent with earlier investigations of analogous silicate compounds are also reported.
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Affiliation(s)
- Travis H Sefzik
- Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, OH 43210-1173, USA
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27
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Tulk CA, Benmore CJ, Klug DD, Neuefeind J. Comment on "Nature of the polyamorphic transition in ice under pressure". PHYSICAL REVIEW LETTERS 2006; 96:149601; discussion 149602. [PMID: 16712130 DOI: 10.1103/physrevlett.96.149601] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2005] [Indexed: 05/09/2023]
Affiliation(s)
- C A Tulk
- Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
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28
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Micoulaut M, Guissani Y, Guillot B. Simulated structural and thermal properties of glassy and liquid germania. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2006; 73:031504. [PMID: 16605529 DOI: 10.1103/physreve.73.031504] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2005] [Revised: 01/10/2006] [Indexed: 05/08/2023]
Abstract
Structural, dynamical, and thermal properties of germanium dioxide are investigated with classical molecular dynamics simulations from the amorphous to the liquid state. Pair correlation functions and coordination numbers are computed under pressure change and show the progressive conversion of the tetrahedral network into an octahedral network, in agreement with experiments. The thermodynamical behavior of the liquid is investigated by means of an equation of state that allows a precise estimation of the compressibility. At low temperature, the diffusion constant D shows an Arrhenius law that progressively deviates when the temperature is increased. The overall comparison with simulated silica permits finally to outline not only the differences in the physical behavior of these two similar systems but also to stress the limitation of the employed germania potential.
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Affiliation(s)
- M Micoulaut
- Laboratoire de Physique Théorique de la Matière Condensée, CNRS UMR 7600, Université Pierre et Marie Curie, Boite 121, 4, Place Jussieu, 75252 Paris Cedex 05, France
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29
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Wilding MC, Wilson M, McMillan PF. Structural studies and polymorphism in amorphous solids and liquids at high pressure. Chem Soc Rev 2006; 35:964-86. [PMID: 17003901 DOI: 10.1039/b517775h] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
When amorphous materials are compressed their structures are expected to change in response to densification. In some cases, the changes in amorphous structure can be discontinuous and they can even have the character of first-order phase transitions. This is a phenomenon referred to as polyamorphism. Most evidence for polyamorphic transitions between low and high density liquids or analogous transformations between amorphous forms of the same substance to date has been indirect and based on the changes in thermodynamic and other structure-related properties with pressure. Recent studies using advanced X-ray and neutron scattering methods combined with molecular dynamics simulations are now revealing the details of structural changes in polyamorphic systems as a function of pressure. Various "two state" or "two species" models are used to understand the anomalous densification behaviour of liquids with melting curve maxima or regions of negative melting slope. Thermodynamic analysis of the two state model leads to the possibility of low- to high-density liquid transitions caused by differences in bulk thermodynamic properties between different amorphous forms and on the degree of cooperativity between low- and high-density structural configurations. The potential occurrence of first-order transitions between supercooled liquids is identified as a critical-like phenomenon. In this tutorial review we discuss the background to polyamorphism, incorporating the experimental observations, simulation studies and the two-state models. We also describe work carried on several systems that are considered to be polyamorphic.
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Affiliation(s)
- Martin C Wilding
- Institute of Mathematic and Physical Sciences, University of Wales at Aberystwyth, Ceredigion SY23 3BZ, UK
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30
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Giacomazzi L, Umari P, Pasquarello A. Medium-range structural properties of vitreous germania obtained through first-principles analysis of vibrational spectra. PHYSICAL REVIEW LETTERS 2005; 95:075505. [PMID: 16196794 DOI: 10.1103/physrevlett.95.075505] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2005] [Indexed: 05/04/2023]
Abstract
We analyze the principal vibrational spectra of vitreous GeO(2) and derive therefrom structural properties referring to length scales beyond the basic tetrahedral unit. We generate a model structure that yields a neutron structure factor in accord with experiment. The inelastic-neutron, the infrared, and the Raman spectra, calculated within a density-functional approach, also agree with respective experimental spectra. The accord for the Raman spectrum supports a Ge-O-Ge angle distribution centered at 135 degrees. The Raman feature X(2) is found to result from vibrations in three-membered rings, and therefore constitutes a distinctive characteristic of the medium-range structure.
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Affiliation(s)
- Luigi Giacomazzi
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Institute of Theoretical Physics, Switzerland
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31
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Guthrie M, Tulk CA, Benmore CJ, Xu J, Yarger JL, Klug DD, Tse JS, Mao HK, Hemley RJ. Formation and structure of a dense octahedral glass. PHYSICAL REVIEW LETTERS 2004; 93:115502. [PMID: 15447351 DOI: 10.1103/physrevlett.93.115502] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2004] [Indexed: 05/24/2023]
Abstract
We have performed in situ x-ray and neutron-diffraction measurements, and molecular dynamics simulations, of GeO2, an archetypal network-forming glass under pressure. Below 5 GPa, additional atoms encroaching on the first tetrahedral shell are seen to be a precursor of local coordination change. Between 6 and 10 GPa, we observe structures with a constant average coordination of approximately 5, indicating a new metastable, intermediate form of the glass. At 15 GPa, the structure of a fully octahedral glass has been measured. This structure is not retained upon decompression and, therefore, must be studied in situ.
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Affiliation(s)
- M Guthrie
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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