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Shimogawa R, Marcella N, O'Connor CR, Kim TS, Reece C, Lubomirsky I, Frenkel AI. Iterative Bragg peak removal on X-ray absorption spectra with automatic intensity correction. JOURNAL OF SYNCHROTRON RADIATION 2024; 31:456-463. [PMID: 38592971 DOI: 10.1107/s1600577524002327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 03/10/2024] [Indexed: 04/11/2024]
Abstract
This study introduces a novel iterative Bragg peak removal with automatic intensity correction (IBR-AIC) methodology for X-ray absorption spectroscopy (XAS), specifically addressing the challenge of Bragg peak interference in the analysis of crystalline materials. The approach integrates experimental adjustments and sophisticated post-processing, including an iterative algorithm for robust calculation of the scaling factor of the absorption coefficients and efficient elimination of the Bragg peaks, a common obstacle in accurately interpreting XAS data, particularly in crystalline samples. The method was thoroughly evaluated on dilute catalysts and thin films, with fluorescence mode and large-angle rotation. The results underscore the technique's effectiveness, adaptability and substantial potential in improving the precision of XAS data analysis. While demonstrating significant promise, the method does have limitations related to signal-to-noise ratio sensitivity and the necessity for meticulous angle selection during experimentation. Overall, IBR-AIC represents a significant advancement in XAS, offering a pragmatic solution to Bragg peak contamination challenges, thereby expanding the applications of XAS in understanding complex materials under diverse experimental conditions.
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Affiliation(s)
- Ryuichi Shimogawa
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, NY 11794, USA
| | - Nicholas Marcella
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, NY 11794, USA
| | | | - Taek Seung Kim
- Harvard University, Rowland Institute at Harvard, Cambridge, MA 02142, USA
| | - Christian Reece
- Harvard University, Rowland Institute at Harvard, Cambridge, MA 02142, USA
| | - Igor Lubomirsky
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 761001, Israel
| | - Anatoly I Frenkel
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, NY 11794, USA
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2
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Hong X, Newville M, Ding Y. Local structural investigation of non-crystalline materials at high pressure: the case of GeO 2glass. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 35:164001. [PMID: 36764002 DOI: 10.1088/1361-648x/acbb4c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 02/10/2023] [Indexed: 06/18/2023]
Abstract
Local structures play a crucial role in the structural polyamorphism and novel electronic properties of amorphous materials, but their accurate measurement at high pressure remains a formidable challenge. In this article, we use the local structure of network-forming GeO2glass as an example, to present our recent approaches and advances in high-energy x-ray diffraction, high-pressure x-ray absorption fine structure, andab initiofirst-principles density functional theory calculations and simulations. Although GeO2glass is one of the best studied materials in the field of high pressure research due to its importance in glass theory and geophysical significance, there are still some long-standing puzzles, such as the existence of appreciable distinct fivefold[5]Ge coordination at low pressure and the sixfold-plus[6+]Ge coordination at ultrahigh pressure. Our work sheds light on the origin of pressure-induced polyamorphism of GeO2glass, and the[5]Ge polyhedral units may be the dominant species in the densification mechanism of network-forming glasses from tetrahedral to octahedral amorphous structures.
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Affiliation(s)
- Xinguo Hong
- Center for High Pressure Science and Technology Advanced Research, Beijing 100193, People's Republic of China
| | - Matt Newville
- Center for Advanced Radiation Sources, University of Chicago, Chicago, IL 60637, United States of America
| | - Yang Ding
- Center for High Pressure Science and Technology Advanced Research, Beijing 100193, People's Republic of China
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3
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Blackmore RH, Rivas ME, Tierney GF, Mohammed KMH, Decarolis D, Hayama S, Venturini F, Held G, Arrigo R, Amboage M, Hellier P, Lynch E, Amri M, Casavola M, Eralp Erden T, Collier P, Wells PP. The electronic structure, surface properties, and in situ N 2O decomposition of mechanochemically synthesised LaMnO 3. Phys Chem Chem Phys 2020; 22:18774-18787. [PMID: 32602489 DOI: 10.1039/d0cp00793e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The use of mechanochemistry to prepare catalytic materials is of significant interest; it offers an environmentally beneficial, solvent-free, route and produces highly complex structures of mixed amorphous and crystalline phases. This study reports on the effect of milling atmosphere, either air or argon, on mechanochemically prepared LaMnO3 and the catalytic performance towards N2O decomposition (deN2O). In this work, high energy resolution fluorescence detection (HERFD), X-ray absorption near edge structure (XANES), X-ray emission, and X-ray photoelectron spectroscopy (XPS) have been used to probe the electronic structural properties of the mechanochemically prepared materials. Moreover, in situ studies using near ambient pressure (NAP)-XPS, to follow the materials during catalysis, and high pressure energy dispersive EXAFS studies, to mimic the preparation conditions, have also been performed. The studies show that there are clear differences between the air and argon milled samples, with the most pronounced changes observed using NAP-XPS. The XPS results find increased levels of active adsorbed oxygen species, linked to the presence of surface oxide vacancies, for the sample prepared in argon. Furthermore, the argon milled LaMnO3 shows improved catalytic activity towards deN2O at lower temperatures compared to the air milled and sol-gel synthesised LaMnO3. Assessing this improved catalytic behaviour during deN2O of argon milled LaMnO3 by in situ NAP-XPS suggests increased interaction of N2O at room temperature within the O 1s region. This study further demonstrates the complexity of mechanochemically prepared materials and through careful choice of characterisation methods how their properties can be understood.
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Affiliation(s)
- Rachel H Blackmore
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratories, Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0FA, UK and School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK.
| | - Maria Elena Rivas
- Johnson Matthey Technology Centre, Blounts Court Road, Sonning Common, Reading, RG4 9NH, UK
| | - George F Tierney
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratories, Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0FA, UK and School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK.
| | - Khaled M H Mohammed
- School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK. and Department of Chemistry, Faculty of Science, Sohag University, Sohag, P. O. Box 82524, Egypt
| | - Donato Decarolis
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratories, Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0FA, UK and School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, UK
| | - Shusaku Hayama
- Diamond Light Source Ltd., Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Federica Venturini
- Diamond Light Source Ltd., Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Georg Held
- Diamond Light Source Ltd., Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Rosa Arrigo
- Diamond Light Source Ltd., Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK and School of Science, Engineering and Environment, University of Salford, Manchester M5 4WT, UK
| | - Monica Amboage
- Diamond Light Source Ltd., Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Pip Hellier
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratories, Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0FA, UK and School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, UK
| | - Evan Lynch
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratories, Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0FA, UK and School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK.
| | - Mahrez Amri
- Johnson Matthey Technology Centre, Blounts Court Road, Sonning Common, Reading, RG4 9NH, UK
| | - Marianna Casavola
- School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK.
| | - Tugce Eralp Erden
- Johnson Matthey Technology Centre, Blounts Court Road, Sonning Common, Reading, RG4 9NH, UK
| | - Paul Collier
- Johnson Matthey Technology Centre, Blounts Court Road, Sonning Common, Reading, RG4 9NH, UK
| | - Peter P Wells
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratories, Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0FA, UK and School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK. and Diamond Light Source Ltd., Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
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4
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Lahiri D, Dwivedi A, Vasanthi R, Jha SN, Garg N. First high-pressure XAFS results at the bending-magnet-based energy-dispersive XAFS beamline BL-8 at the Indus-2 synchrotron facility. JOURNAL OF SYNCHROTRON RADIATION 2020; 27:988-998. [PMID: 33566008 DOI: 10.1107/s1600577520006098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 05/04/2020] [Indexed: 06/12/2023]
Abstract
The static focusing optics of the existing energy-dispersive XAFS beamline BL-8 have been advantageously exploited to initiate diamond anvil cell based high-pressure XANES experiments at the Indus-2 synchrotron facility, India. In the framework of the limited photon statistics with the 2.5 GeV bending-magnet source, limited focusing optics and 4 mm-thick diamond windows of the sample cell, a (non-trivial) beamline alignment method for maximizing photon statistics at the sample position has been designed. Key strategies include the selection of a high X-ray energy edge, the truncation of the smallest achievable focal spot size to target size with a slit and optimization of the horizontal slit position for transmission of the desired energy band. A motor-scanning program for precise sample centering has been developed. These details are presented with rationalization for every step. With these strategies, Nb K-edge XANES spectra for Nb2O5 under high pressure (0-16.9 GPa) have been generated, reproducing the reported spectra for Nb2O5 under ambient conditions and high pressure. These first HPXANES results are reported in this paper. The scope of extending good data quality to the EXAFS range in the future is addressed. This work should inspire and guide future high-pressure XAFS experiments with comparable infrastructure.
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Affiliation(s)
- Debdutta Lahiri
- High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - Ashutosh Dwivedi
- Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - R Vasanthi
- High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - S N Jha
- Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - Nandini Garg
- High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
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5
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Bai F, Bian K, Huang X, Wang Z, Fan H. Pressure Induced Nanoparticle Phase Behavior, Property, and Applications. Chem Rev 2019; 119:7673-7717. [PMID: 31059242 DOI: 10.1021/acs.chemrev.9b00023] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Nanoparticle (NP) high pressure behavior has been extensively studied over the years. In this review, we summarize recent progress on the studies of pressure induced NP phase behavior, property, and applications. This review starts with a brief overview of high pressure characterization techniques, coupled with synchrotron X-ray scattering, Raman, fluorescence, and absorption. Then, we survey the pressure induced phase transition of NP atomic crystal structure including size dependent phase transition, amorphization, and threshold pressures using several typical NP material systems as examples. Next, we discuss the pressure induced phase transition of NP mesoscale structures including topics on pressure induced interparticle separation distance, NP coupling, and NP coalescence. Pressure induced new properties and applications in different NP systems are highlighted. Finally, outlooks with future directions are discussed.
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Affiliation(s)
- Feng Bai
- Key Laboratory for Special Functional Materials of the Ministry of Education, Henan University, Kaifeng 475004, P. R. China
| | - Kaifu Bian
- Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - Xin Huang
- Cornell High Energy Synchrotron Source, Cornell University, Ithaca, New York 14853, United States
| | - Zhongwu Wang
- Cornell High Energy Synchrotron Source, Cornell University, Ithaca, New York 14853, United States
| | - Hongyou Fan
- Sandia National Laboratories, Albuquerque, New Mexico 87185, United States.,Department of Chemical and Biological Engineering, Albuquerque, University of New Mexico, Albuquerque, New Mexico 87106, United States.,Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
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6
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Dong J, Yao H, Guo Z, Jia Q, Wang Y, An P, Gong Y, Liang Y, Chen D. Revisiting local structural changes in GeO 2 glass at high pressure. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:465401. [PMID: 29053477 DOI: 10.1088/1361-648x/aa8d50] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Despite the great importance in fundamental and industrial fields, understanding structural changes for pressure-induced polyamorphism in network-forming glasses remains a formidable challenge. Here, we revisited the local structural transformations in GeO2 glass up to 54 GPa using x-ray absorption fine structure (XAFS) spectroscopy via a combination diamond anvil cell and polycapillary half-lens. Three polyamorphic transitions can be clearly identified by XAFS structure refinement. First, a progressive increase of the nearest Ge-O distance and bond disorder to a maximum at ~5-16 GPa, in the same pressure region of previously observed tetrahedral-octahedral transformation. Second, a marked decrease of the nearest Ge-O distance at ~16-22.6 GPa but a slight increase at ~22.6-32.7 GPa, with a concomitant decrease of bond disorder. This stage can be related to a second-order-like transition from less dense to dense octahedral glass. Third, another decrease in the nearest Ge-O distance at ~32.7-41.4 GPa but a slight increase up to 54 GPa, synchronized with a gradual increase of bond disorder. This stage provides strong evidence for ultrahigh-pressure polyamorphism with coordination number >6. Furthermore, cooperative modification is observed in more distant shells. Those results provide a unified local structural picture for elucidating the polyamorphic transitions and densification process in GeO2 glass.
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Affiliation(s)
- Juncai Dong
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, People's Republic of China
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7
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Shen G, Mao HK. High-pressure studies with x-rays using diamond anvil cells. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2017; 80:016101. [PMID: 27873767 DOI: 10.1088/1361-6633/80/1/016101] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Pressure profoundly alters all states of matter. The symbiotic development of ultrahigh-pressure diamond anvil cells, to compress samples to sustainable multi-megabar pressures; and synchrotron x-ray techniques, to probe materials' properties in situ, has enabled the exploration of rich high-pressure (HP) science. In this article, we first introduce the essential concept of diamond anvil cell technology, together with recent developments and its integration with other extreme environments. We then provide an overview of the latest developments in HP synchrotron techniques, their applications, and current problems, followed by a discussion of HP scientific studies using x-rays in the key multidisciplinary fields. These HP studies include: HP x-ray emission spectroscopy, which provides information on the filled electronic states of HP samples; HP x-ray Raman spectroscopy, which probes the HP chemical bonding changes of light elements; HP electronic inelastic x-ray scattering spectroscopy, which accesses high energy electronic phenomena, including electronic band structure, Fermi surface, excitons, plasmons, and their dispersions; HP resonant inelastic x-ray scattering spectroscopy, which probes shallow core excitations, multiplet structures, and spin-resolved electronic structure; HP nuclear resonant x-ray spectroscopy, which provides phonon densities of state and time-resolved Mössbauer information; HP x-ray imaging, which provides information on hierarchical structures, dynamic processes, and internal strains; HP x-ray diffraction, which determines the fundamental structures and densities of single-crystal, polycrystalline, nanocrystalline, and non-crystalline materials; and HP radial x-ray diffraction, which yields deviatoric, elastic and rheological information. Integrating these tools with hydrostatic or uniaxial pressure media, laser and resistive heating, and cryogenic cooling, has enabled investigations of the structural, vibrational, electronic, and magnetic properties of materials over a wide range of pressure-temperature conditions.
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Affiliation(s)
- Guoyin Shen
- Geophysical Laboratory, Carnegie Institution of Washington, Washington DC, USA
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8
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Corsini NRC, Zhang Y, Little WR, Karatutlu A, Ersoy O, Haynes PD, Molteni C, Hine NDM, Hernandez I, Gonzalez J, Rodriguez F, Brazhkin VV, Sapelkin A. Pressure-Induced Amorphization and a New High Density Amorphous Metallic Phase in Matrix-Free Ge Nanoparticles. NANO LETTERS 2015; 15:7334-7340. [PMID: 26457875 DOI: 10.1021/acs.nanolett.5b02627] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Over the last two decades, it has been demonstrated that size effects have significant consequences for the atomic arrangements and phase behavior of matter under extreme pressure. Furthermore, it has been shown that an understanding of how size affects critical pressure-temperature conditions provides vital guidance in the search for materials with novel properties. Here, we report on the remarkable behavior of small (under ~5 nm) matrix-free Ge nanoparticles under hydrostatic compression that is drastically different from both larger nanoparticles and bulk Ge. We discover that the application of pressure drives surface-induced amorphization leading to Ge-Ge bond overcompression and eventually to a polyamorphic semiconductor-to-metal transformation. A combination of spectroscopic techniques together with ab initio simulations were employed to reveal the details of the transformation mechanism into a new high density phase-amorphous metallic Ge.
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Affiliation(s)
- Niccolo R C Corsini
- Department of Physics, Blackett Laboratory, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
| | - Yuanpeng Zhang
- School of Physics and Astronomy, Queen Mary University of London , Mile End Road, London E1 4NS, United Kingdom
| | - William R Little
- School of Physics and Astronomy, Queen Mary University of London , Mile End Road, London E1 4NS, United Kingdom
| | - Ali Karatutlu
- School of Physics and Astronomy, Queen Mary University of London , Mile End Road, London E1 4NS, United Kingdom
- Electrical and Electronics Engineering, Yildirim Campus, Bursa Orhangazi University , 16245 Yildirim, Bursa, Turkey
| | - Osman Ersoy
- School of Physics and Astronomy, Queen Mary University of London , Mile End Road, London E1 4NS, United Kingdom
| | - Peter D Haynes
- Department of Physics, Blackett Laboratory, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
| | - Carla Molteni
- Department of Physics, King's College London , Strand, London WC2R 2LS, United Kingdom
| | - Nicholas D M Hine
- TCM Group, Cavendish Laboratory, University of Cambridge , JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
- Department of Physics, University of Warwick , Coventry CV4 7AL, United Kingdom
| | - Ignacio Hernandez
- Malta Consolider Team, Departmento CITIMAC, Universidad de Cantabria , Avenida Los Castros s/n, 39005 Santander, Spain
| | - Jesus Gonzalez
- Malta Consolider Team, Departmento CITIMAC, Universidad de Cantabria , Avenida Los Castros s/n, 39005 Santander, Spain
| | - Fernando Rodriguez
- Malta Consolider Team, Departmento CITIMAC, Universidad de Cantabria , Avenida Los Castros s/n, 39005 Santander, Spain
| | - Vadim V Brazhkin
- High Pressure Physics Institute, RAS , 142190 Troitsk, Moscow Region, Russia
| | - Andrei Sapelkin
- School of Physics and Astronomy, Queen Mary University of London , Mile End Road, London E1 4NS, United Kingdom
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9
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Hong X, Newville M, Duffy TS, Sutton SR, Rivers ML. X-ray absorption spectroscopy of GeO2 glass to 64 GPa. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:035104. [PMID: 24285424 DOI: 10.1088/0953-8984/26/3/035104] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The structural behavior of GeO2 glass has been investigated up to 64 GPa using results from x-ray absorption spectroscopy in a diamond anvil cell combined with previously reported density measurements. The difference between the nearest Ge-O distances of glassy and rutile-type GeO2 disappears at the Ge-O distance maximum at 20 GPa, indicating completion of the tetrahedral-octahedral transition in GeO2 glass. The mean-square displacement σ(2) of the Ge-O distance in the first Ge-O shell increases progressively to a maximum at 10 GPa, followed by a substantial reduction at higher pressures. The octahedral glass is, as expected, less dense and has a higher compressibility than the corresponding crystalline phase, but the differences in Ge-O distance and density between the glass and the crystals are gradually eliminated over the 20-40 GPa pressure range. Above 40 GPa, GeO2 forms a dense octahedral glass with a compressibility similar to that of the corresponding crystalline phase (α-PbO2 type). The EXAFS and XANES spectra show evidence for subtle changes in the dense glass continuing to occur at these high pressures. The Ge-O bond distance shows little change between 45-64 GPa, and this may reflect a balance between bond shortening and a gradual coordination number increase with compression. The density of the glass is similar to that of the α-PbO2-type phase, but the Ge-O distance is longer and is close to that in the higher-coordination pyrite-type phase which is stable above ∼60 GPa. The density data provide evidence for a possible discontinuity and change in compressibility at 40-45 GPa, but there are no major changes in the corresponding EXAFS spectra. A pyrite-type local structural model for the glass can provide a reasonable fitting to the XAFS spectra at 64 GPa.
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Affiliation(s)
- Xinguo Hong
- Mineral Physics Institute, Stony Brook University, Stony Brook, NY 11794, USA
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10
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Ravel B, Attenkofer K, Bohon J, Muller E, Smedley J. Diamond sensors and polycapillary lenses for X-ray absorption spectroscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:103106. [PMID: 24182100 DOI: 10.1063/1.4824350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Diamond sensors are evaluated as incident beam monitors for X-ray absorption spectroscopy experiments. These single crystal devices pose a challenge for an energy-scanning experiment using hard X-rays due to the effect of diffraction from the crystalline sensor at energies which meet the Bragg condition. This problem is eliminated by combination with polycapillary lenses. The convergence angle of the beam exiting the lens is large compared to rocking curve widths of the diamond. A ray exiting one capillary from the lens meets the Bragg condition for any reflection at a different energy from the rays exiting adjacent capillaries. This serves to broaden each diffraction peak over a wide energy range, allowing linear measurement of incident intensity over the range of the energy scan. Extended X-ray absorption fine structure data are measured with a combination of a polycapillary lens and a diamond incident beam monitor. These data are of comparable quality to data measured without a lens and with an ionization chamber monitoring the incident beam intensity.
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Affiliation(s)
- B Ravel
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
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11
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Chen D, Dong J, Zhang X, Quan P, Liang Y, Hu T, Liu J, Wu X, Zhang Q, Li Y. Suppression of Bragg reflection glitches of a single-crystal diamond anvil cell by a polycapillary half-lens in high-pressure XAFS spectroscopy. JOURNAL OF SYNCHROTRON RADIATION 2013; 20:243-248. [PMID: 23412480 DOI: 10.1107/s0909049513000265] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 01/03/2013] [Indexed: 06/01/2023]
Abstract
In combination with a single-crystal diamond anvil cell (DAC), a polycapillary half-lens (PHL) re-focusing optics has been used to perform high-pressure extended X-ray absorption fine-structure measurements. It is found that a large divergent X-ray beam induced by the PHL leads the Bragg glitches from single-crystal diamond to be broadened significantly and the intensity of the glitches to be reduced strongly so that most of the DAC glitches are efficiently suppressed. The remaining glitches can be easily removed by rotating the DAC by a few degrees with respect to the X-ray beam. Accurate X-ray absorption fine-structure (XAFS) spectra of polycrystalline Ge powder with a glitch-free energy range from -200 to 800 eV relative to the Ge absorption edge are obtained using this method at high pressures up to 23.7 GPa, demonstrating the capability of PHL optics in eliminating the DAC glitches for high-pressure XAFS experiments. This approach brings new possibilities to perform XAFS measurements using a DAC up to ultrahigh pressures.
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Affiliation(s)
- Dongliang Chen
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, People's Republic of China
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12
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Ishimatsu N, Matsumoto K, Maruyama H, Kawamura N, Mizumaki M, Sumiya H, Irifune T. Glitch-free X-ray absorption spectrum under high pressure obtained using nano-polycrystalline diamond anvils. JOURNAL OF SYNCHROTRON RADIATION 2012; 19:768-72. [PMID: 22898956 PMCID: PMC3621395 DOI: 10.1107/s0909049512026088] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Accepted: 06/08/2012] [Indexed: 05/31/2023]
Abstract
Nano-polycrystalline diamond (NPD) [Irifune et al. (2003), Nature (London), 421, 599] has been used to obtain a glitch-free X-ray absorption spectrum under high pressure. In the case of conventional single-crystal diamond (SCD) anvils, glitches owing to Bragg diffraction from the anvils are superimposed on X-ray absorption spectra. The glitch has long been a serious problem for high-pressure research activities using X-ray spectroscopy because of the difficulties of its complete removal. It is demonstrated that NPD is one of the best candidate materials to overcome this problem. Here a glitch-free absorption spectrum using the NPD anvils over a wide energy range is shown. The advantage and capability of NPD anvils is discussed by a comparison of the glitch map with that of SCD anvils.
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Affiliation(s)
- Naoki Ishimatsu
- Department of Physics, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima 739-8526, Japan.
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13
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Hong X, Chen Z, Duffy TS. Absolute x-ray energy calibration over a wide energy range using a diffraction-based iterative method. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:063901. [PMID: 22755637 DOI: 10.1063/1.4722166] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In this paper, we report a method of precise and fast absolute x-ray energy calibration over a wide energy range using an iterative x-ray diffraction based method. Although accurate x-ray energy calibration is indispensable for x-ray energy-sensitive scattering and diffraction experiments, there is still a lack of effective methods to precisely calibrate energy over a wide range, especially when normal transmission monitoring is not an option and complicated micro-focusing optics are fixed in place. It is found that by using an iterative algorithm the x-ray energy is only tied to the relative offset of sample-to-detector distance, which can be readily varied with high precision of the order of 10(-5) -10(-6) spatial resolution using gauge blocks. Even starting with arbitrary initial values of 0.1 Å, 0.3 Å, and 0.4 Å, the iteration process converges to a value within 3.5 eV for 31.122 keV x-rays after three iterations. Different common diffraction standards CeO(2), Au, and Si show an energy deviation of 14 eV. As an application, the proposed method has been applied to determine the energy-sensitive first sharp diffraction peak of network forming GeO(2) glass at high pressure, exhibiting a distinct behavior in the pressure range of 2-4 GPa. Another application presented is pair distribution function measurement using calibrated high-energy x-rays at 82.273 keV. Unlike the traditional x-ray absorption-based calibration method, the proposed approach does not rely on any edges of specific elements, and is applicable to the hard x-ray region where no appropriate absorption edge is available.
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Affiliation(s)
- Xinguo Hong
- Mineral Physics Institute, Stony Brook University, Stony Brook, New York 11794, USA.
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Chu S, Zheng L, Zhou Y, Zhou A, Zhang J, Che R, Liu J, Hu T. The measurement of differential EXAFS modulated by high pressure. JOURNAL OF SYNCHROTRON RADIATION 2011; 18:728-732. [PMID: 21862852 DOI: 10.1107/s0909049511023442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Accepted: 06/16/2011] [Indexed: 05/31/2023]
Abstract
Differential EXAFS (DiffEXAFS) is able to detect subtle atomic perturbations in the local area of the absorbing atom. Here a new method of performing DiffEXAFS experiments under the modulation of high pressure has been developed. Periodic pressure was achieved in the gasket with the help of a dynamic diamond anvil cell, and the measurements were conducted in common energy-scanning mode. This technique has been utilized on ZnSe at 4.8 GPa. The present results have demonstrated a good agreement with the equation of state of ZnSe, and revealed sensitivity to atomic displacements of one order higher in magnitude than that of conventional EXAFS.
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Affiliation(s)
- Shengqi Chu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, People's Republic of China
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Marrocchelli D, Salanne M, Madden PA. High-pressure behaviour of GeO2: a simulation study. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:152102. [PMID: 21389544 DOI: 10.1088/0953-8984/22/15/152102] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this work we study the high-pressure behaviour of liquid and glassy GeO(2) by means of molecular dynamics simulations. The interaction potential, which includes dipole polarization effects, was parametrized using first-principles calculations. Our simulations reproduce the most recent experimental structural data very well. The character of the pressure-induced structural transition in the glassy system has been a matter of controversy. We show that our simulations and the experimental data are consistent with a smooth transition from a tetrahedral to an octahedral network with a significant number of pentacoordinated germanium ions appearing over an extended pressure range. Finally, the study of high-pressure, liquid germania confirms that this material presents an anomalous behaviour of the diffusivity as observed in analogous systems such as silica and water. The importance of pentacoordinated germanium ions for such behaviour is stressed.
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