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Wilding MC, Sella A, Howard CA, Sobrido AJ, Catlow CRA. Exploring the length scales, timescales and chemistry of challenging materials (Part 2). Philos Trans A Math Phys Eng Sci 2023; 381:20230175. [PMID: 37691460 PMCID: PMC10493547 DOI: 10.1098/rsta.2023.0175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 08/09/2023] [Indexed: 09/12/2023]
Abstract
This themed issue explores the different length and timescales that determine the physics and chemistry of a variety of key of materials, explored from the perspective of a wide range of disciplines, including physics, chemistry materials science, Earth science and biochemistry. The topics discussed include catalysis, chemistry under extreme conditions, energy materials, amorphous and liquid structure, hybrid organic materials and biological materials. The issue is in two parts, with this second set of contributions exploring hybrid organic materials, catalysis low-dimensional and graphitic materials, biological materials and naturally occurring, super-hard material as well as dynamic high pressure and new developments in imaging techniques pressure. This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 2)'.
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Affiliation(s)
- Martin C. Wilding
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratory, Oxfordshire OX11, 0QX, UK
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff CF10 3AT, UK
| | - Andrea Sella
- Department of Chemistry, University College London, London WC1E 6BT, UK
| | | | - Ana Jorge Sobrido
- School of Engineering and Materials Science, Queen Mary University of London, London E1 4NS, UK
| | - C. R. A. Catlow
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratory, Oxfordshire OX11, 0QX, UK
- Department of Chemistry, University College London, London WC1E 6BT, UK
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff CF10 3AT, UK
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2
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Dervin D, O'Malley AJ, Falkowska M, Chansai S, Silverwood IP, Hardacre C, Catlow CRA. Probing the dynamics and structure of confined benzene in MCM-41 based catalysts. Phys Chem Chem Phys 2020; 22:11485-11489. [DOI: 10.1039/d0cp01196g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Combined MD simulations and QENS experiments on benzene in MCM-41 provide insight into the dynamics and structure of benzene
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Affiliation(s)
- Daniel Dervin
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
- UK Catalysis Hub
| | - A. J. O'Malley
- Centre for Sustainable Chemical Technologies
- Department of Chemistry
- University of Bath
- Claverton Down
- UK
| | - Marta Falkowska
- Department of Chemical Engineering and Analytical Science, School of Engineering
- The University of Manchester
- Manchester
- UK
| | - Sarayute Chansai
- Department of Chemical Engineering and Analytical Science, School of Engineering
- The University of Manchester
- Manchester
- UK
| | | | - Christopher Hardacre
- UK Catalysis Hub
- Research Complex at Harwell
- Rutherford Appleton Laboratory
- Harwell OX11 0FA
- UK
| | - C. R. A. Catlow
- UK Catalysis Hub
- Research Complex at Harwell
- Rutherford Appleton Laboratory
- Harwell OX11 0FA
- UK
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3
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Venezia B, Cao E, Matam SK, Waldron C, Cibin G, Gibson EK, Golunski S, Wells PP, Silverwood I, Catlow CRA, Sankar G, Gavriilidis A. Silicon microfabricated reactor for operando XAS/DRIFTS studies of heterogeneous catalytic reactions. Catal Sci Technol 2020. [DOI: 10.1039/d0cy01608j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel microreactor for operando XAS and DRIFTS studies of catalytic reactions is reported, exhibiting plug-flow, isothermal behaviour and absence of mass transfer resistances and dead volume, enabling time- and spatially-resolved experiments.
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4
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Nastase SAF, O’Malley AJ, Catlow CRA, Logsdail AJ. Computational QM/MM investigation of the adsorption of MTH active species in H-Y and H-ZSM-5. Phys Chem Chem Phys 2019; 21:2639-2650. [PMID: 30657492 DOI: 10.1039/c8cp06736h] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The transformation of methanol-to-hydrocarbons (MTH) has significant potential as a route to synthesise low-cost fuels; however, the initial stages of the zeolite catalysed MTH process are not well understood.
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Affiliation(s)
- S. A. F. Nastase
- Cardiff Catalysis Institute
- School of Chemistry
- Cardiff University
- UK
| | - A. J. O’Malley
- UK Catalysis Hub
- Research Complex at Harwell, Science and Technology Facilities Council Rutherford Appleton Laboratory
- Harwell Science and Innovation Campus
- Oxon
- UK
| | - C. R. A. Catlow
- Cardiff Catalysis Institute
- School of Chemistry
- Cardiff University
- UK
- UK Catalysis Hub
| | - A. J. Logsdail
- Cardiff Catalysis Institute
- School of Chemistry
- Cardiff University
- UK
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5
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Aniagyei A, Dzade NY, Tia R, Adei E, Catlow CRA, de Leeuw NH. Ab initio investigation of O 2 adsorption on Ca-doped LaMnO 3 cathodes in solid oxide fuel cells. Phys Chem Chem Phys 2018; 20:28685-28698. [PMID: 30411098 DOI: 10.1039/c8cp02137f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a Hubbard-corrected density functional theory (DFT+U) study of the adsorption and reduction reactions of oxygen on the pure and 25% Ca-doped LaMnO3 (LCM25) {100} and {110} surfaces. The effect of oxygen vacancies on the adsorption characteristics and energetics has also been investigated. Our results show that the O2 adsorption/reduction process occurs through the formation of superoxide and peroxide intermediates, with the Mn sites found to be generally more active than the La sites. The LCM25{110} surface is found to be more efficient for O2 reduction than the LCM25{100} surface due to its stronger adsorption of O2, with the superoxide and peroxide intermediates shown to be energetically more favorable at the Mn sites than at the Ca sites. Moreover, oxygen vacancy defect sites on both the {100} and {110} surfaces are shown to be more efficient for O2 reduction, as reflected in the higher adsorption energies calculated on the defective surfaces compared to the perfect surfaces. We show from Löwdin population analysis that the O2 adsorption on the pure and 25% Ca-doped LaMnO3 surfaces is characterized by charge transfer from the interacting surface species into the adsorbed oxygen πg orbital, which results in weakening of the O-O bonds and its subsequent reduction. The elongated O-O bonds were confirmed via vibrational frequency analysis.
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Affiliation(s)
- Albert Aniagyei
- Department of Chemistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
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O'Malley AJ, Sarwar M, Armstrong J, Catlow CRA, Silverwood IP, York APE, Hitchcock I. Comparing ammonia diffusion in NH 3-SCR zeolite catalysts: a quasielastic neutron scattering and molecular dynamics simulation study. Phys Chem Chem Phys 2018; 20:11976-11986. [PMID: 29670963 DOI: 10.1039/c8cp01022f] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The diffusion of ammonia in the small pore zeolite and potential commercial NH3-SCR catalyst levynite (LEV) was measured and compared with its mobility in the chabazite (CHA) topology (more established in NOx abatement catalysis), using quasielastic neutron scattering (QENS) and molecular dynamics (MD) simulations at 273, 323 and 373 K. The QENS experiments suggest that mobility in LEV is dominated by jump diffusion through the 8-ring windows between cages (as previously observed in CHA) which takes place at very similar rates in the two zeolites, yielding similar experimental self-diffusion coefficients (Ds). After confirming that the same characteristic motions are observed between the MD simulations and the QENS experiments on the picosecond scale, the simulations suggest that on the nanoscale, the diffusivity is higher by a factor of ∼2 in the CHA framework than in LEV. This difference between zeolites is primarily explained by the CHA cages having six 8-ring windows in the building unit, compared to only three such windows in the LEV cage building unit, thereby doubling the geometric opportunities to perform jump diffusion between cages (as characterised by the QENS experiments) leading to the corresponding increase in the MD calculated Ds. The techniques illustrate the importance of probing both pico- and nanoscale dynamics when studying intracrystalline diffusion in both NH3-SCR catalyst design, and in porous materials generally, where notable consistencies and differences may be found on either scale.
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Affiliation(s)
- A J O'Malley
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, UK. and UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0FA, UK
| | - M Sarwar
- Johnson Matthey Technology Centre, Blounts Court, Sonning Common, Reading RG4 9NH, UK.
| | - J Armstrong
- ISIS Facility, STFC Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX, UK
| | - C R A Catlow
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, UK. and UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0FA, UK and University College London, Department of Chemistry, Materials Chemistry, Third Floor, Kathleen Lonsdale Building, Gower Street, London WC1E 6BT, UK
| | - I P Silverwood
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0FA, UK and ISIS Facility, STFC Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX, UK
| | - A P E York
- Johnson Matthey Technology Centre, Blounts Court, Sonning Common, Reading RG4 9NH, UK.
| | - I Hitchcock
- Johnson Matthey Technology Centre, Blounts Court, Sonning Common, Reading RG4 9NH, UK.
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O'Malley AJ, Logsdail AJ, Sokol AA, Catlow CRA. Modelling metal centres, acid sites and reaction mechanisms in microporous catalysts. Faraday Discuss 2018; 188:235-55. [PMID: 27136967 DOI: 10.1039/c6fd00010j] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We discuss the role of QM/MM (embedded cluster) computational techniques in catalytic science, in particular their application to microporous catalysis. We describe the methodologies employed and illustrate their utility by briefly summarising work on metal centres in zeolites. We then report a detailed investigation into the behaviour of methanol at acidic sites in zeolites H-ZSM-5 and H-Y in the context of the methanol-to-hydrocarbons/olefins process. Studying key initial steps of the reaction (the adsorption and subsequent methoxylation), we probe the effect of framework topology and Brønsted acid site location on the energetics of these initial processes. We find that although methoxylation is endothermic with respect to the adsorbed system (by 17-56 kJ mol(-1) depending on the location), there are intriguing correlations between the adsorption/reaction energies and the geometries of the adsorbed species, of particular significance being the coordination of methyl hydrogens. These observations emphasise the importance of adsorbate coordination with the framework in zeolite catalysed conversions, and how this may vary with framework topology and site location, particularly suited to investigation by QM/MM techniques.
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Affiliation(s)
- Alexander J O'Malley
- Department of Chemistry, University College London, 20 Gordon St., London WC1 HOAJ, UK and UK Catalysis Hub, Research Complex at Harwell, Science and Technology Facilities Council Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxon OX11 0QX, UK
| | - A J Logsdail
- Department of Chemistry, University College London, 20 Gordon St., London WC1 HOAJ, UK and Cardiff Catalysis Institute, School of Chemistry, Cardiff University, CF10 3AT, UK
| | - A A Sokol
- Department of Chemistry, University College London, 20 Gordon St., London WC1 HOAJ, UK
| | - C R A Catlow
- Department of Chemistry, University College London, 20 Gordon St., London WC1 HOAJ, UK and Cardiff Catalysis Institute, School of Chemistry, Cardiff University, CF10 3AT, UK and UK Catalysis Hub, Research Complex at Harwell, Science and Technology Facilities Council Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxon OX11 0QX, UK
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8
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Matam SK, O'Malley AJ, Catlow CRA, Suwardiyanto S, Collier P, Hawkins AP, Zachariou A, Lennon D, Silverwood I, Parker SF, Howe RF. The effects of MTG catalysis on methanol mobility in ZSM-5. Catal Sci Technol 2018. [DOI: 10.1039/c8cy00422f] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
QENS shows that methanol is immobile in a fresh ZSM-5 catalyst and one used for methanol conversion at 623 K, but undergoes isotropic rotation within the mesopores generated in a catalyst used for methanol conversion at 673 K.
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Affiliation(s)
- S. K. Matam
- Department of Chemistry
- University College London
- UK
- UK Catalysis Hub
- Research Complex at Harwell
| | - A. J. O'Malley
- UK Catalysis Hub
- Research Complex at Harwell
- STFC Rutherford Appleton Laboratory
- Chilton
- UK
| | - C. R. A. Catlow
- UK Catalysis Hub
- Research Complex at Harwell
- STFC Rutherford Appleton Laboratory
- Chilton
- UK
| | | | - P. Collier
- Johnson-Matthey Technology Centre
- Sonning Common
- UK
| | - A. P. Hawkins
- School of Chemistry
- University of Glasgow
- Glasgow G12 8QQ
- UK
| | - A. Zachariou
- School of Chemistry
- University of Glasgow
- Glasgow G12 8QQ
- UK
| | - D. Lennon
- School of Chemistry
- University of Glasgow
- Glasgow G12 8QQ
- UK
| | - I. Silverwood
- ISIS Facility
- STFC Rutherford Appleton Laboratory
- Chilton OX11 0QX
- UK
| | - S. F. Parker
- UK Catalysis Hub
- Research Complex at Harwell
- STFC Rutherford Appleton Laboratory
- Chilton
- UK
| | - R. F. Howe
- Chemistry Department
- University of Aberdeen
- UK
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9
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Silverwood IP, Rogers SM, Callear SK, Parker SF, Catlow CRA. Correction: Evidence for a surface gold hydride on a nanostructured gold catalyst. Chem Commun (Camb) 2016; 52:2412. [PMID: 26790129 DOI: 10.1039/c6cc90049f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Correction for 'Evidence for a surface gold hydride on a nanostructured gold catalyst' by I. P. Silverwood et al., Chem. Commun., 2016, 52, 533-536.
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Affiliation(s)
- I P Silverwood
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0FA, UK and ISIS Facility, STFC Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX, UK.
| | - S M Rogers
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0FA, UK and Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
| | - S K Callear
- ISIS Facility, STFC Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX, UK.
| | - S F Parker
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0FA, UK and ISIS Facility, STFC Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX, UK.
| | - C R A Catlow
- UK Catalysis Hub, Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0FA, UK and Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
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10
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Silverwood IP, Al-Rifai N, Cao E, Nelson DJ, Chutia A, Wells PP, Nolan SP, Frogley MD, Cinque G, Gavriilidis A, Catlow CRA. Towards microfluidic reactors for in situ synchrotron infrared studies. Rev Sci Instrum 2016; 87:024101. [PMID: 26931867 DOI: 10.1063/1.4941825] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Anodically bonded etched silicon microfluidic devices that allow infrared spectroscopic measurement of solutions are reported. These extend spatially well-resolved in situ infrared measurement to higher temperatures and pressures than previously reported, making them useful for effectively time-resolved measurement of realistic catalytic processes. A data processing technique necessary for the mitigation of interference fringes caused by multiple reflections of the probe beam is also described.
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Affiliation(s)
- I P Silverwood
- Department of Chemistry, University College London, London, WC1H 0AJ, United Kingdom
| | - N Al-Rifai
- Department of Chemical Engineering, University College London, London WC1E 7JE, United Kingdom
| | - E Cao
- Department of Chemical Engineering, University College London, London WC1E 7JE, United Kingdom
| | - D J Nelson
- Department of Pure & Applied Chemistry, University of Strathclyde, Glasgow G1 1XL, United Kingdom
| | - A Chutia
- Department of Chemistry, University College London, London, WC1H 0AJ, United Kingdom
| | - P P Wells
- Department of Chemistry, University College London, London, WC1H 0AJ, United Kingdom
| | - S P Nolan
- EaSTCHEM School of Chemistry, University of St Andrews, St Andrews KY16 9ST, United Kingdom
| | - M D Frogley
- Diamond Light Source Ltd, Diamond House, Harwell Science and Innovation Campus, OX11 0DE Didcot, United Kingdom
| | - G Cinque
- Diamond Light Source Ltd, Diamond House, Harwell Science and Innovation Campus, OX11 0DE Didcot, United Kingdom
| | - A Gavriilidis
- Department of Chemical Engineering, University College London, London WC1E 7JE, United Kingdom
| | - C R A Catlow
- Department of Chemistry, University College London, London, WC1H 0AJ, United Kingdom
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Silverwood IP, Rogers SM, Callear SK, Parker SF, Catlow CRA. Evidence for a surface gold hydride on a nanostructured gold catalyst. Chem Commun (Camb) 2016; 52:533-6. [PMID: 26535487 DOI: 10.1039/c5cc06118k] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Inelastic neutron scattering and isotopic infrared spectroscopy shows formation of surface Au–H, an important intermediate in catalytic mechanisms.
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Affiliation(s)
- I. P. Silverwood
- UK Catalysis Hub
- Research Complex at Harwell
- Rutherford Appleton Laboratory
- Didcot
- UK
| | - S. M. Rogers
- UK Catalysis Hub
- Research Complex at Harwell
- Rutherford Appleton Laboratory
- Didcot
- UK
| | - S. K. Callear
- ISIS Facility
- STFC Rutherford Appleton Laboratory
- Didcot
- UK
| | - S. F. Parker
- UK Catalysis Hub
- Research Complex at Harwell
- Rutherford Appleton Laboratory
- Didcot
- UK
| | - C. R. A. Catlow
- UK Catalysis Hub
- Research Complex at Harwell
- Rutherford Appleton Laboratory
- Didcot
- UK
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12
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Catlow CRA. Recent developments in the structural science of materials. IUCrJ 2015; 2:384-6. [PMID: 26175897 PMCID: PMC4491309 DOI: 10.1107/s2052252515010891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This Editorial surveys the current status and recent developments in the structural science of materials as exemplified by the articles recently published in IUCrJ.
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Affiliation(s)
- C. R. A. Catlow
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
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Abstract
The methane C-H bond is extremely stable, requiring significant energy input in reforming processes. We present a novel mechanism for energetically favourable methane C-H bond breaking over yttrium stabilised zirconia in the presence of oxygen, based on results of Density Functional Theory (DFT) and HSE06 hybrid functional calculations. We argue that this mechanism will be relevant to C-H activation over many metal oxide catalyst materials.
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Affiliation(s)
- C S Cooper
- Department of Chemistry, University College London, Gower Street, London, UK.
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14
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Buckeridge J, Catlow CRA, Scanlon DO, Keal TW, Sherwood P, Miskufova M, Walsh A, Woodley SM, Sokol AA. Determination of the nitrogen vacancy as a shallow compensating center in GaN doped with divalent metals. Phys Rev Lett 2015; 114:016405. [PMID: 25615487 DOI: 10.1103/physrevlett.114.016405] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Indexed: 05/25/2023]
Abstract
We report accurate energetics of defects introduced in GaN on doping with divalent metals, focusing on the technologically important case of Mg doping, using a model that takes into consideration both the effect of hole localization and dipolar polarization of the host material, and includes a well-defined reference level. Defect formation and ionization energies show that divalent dopants are counterbalanced in GaN by nitrogen vacancies and not by holes, which explains both the difficulty in achieving p-type conductivity in GaN and the associated major spectroscopic features, including the ubiquitous 3.46 eV photoluminescence line, a characteristic of all lightly divalent-metal-doped GaN materials that has also been shown to occur in pure GaN samples. Our results give a comprehensive explanation for the observed behavior of GaN doped with low concentrations of divalent metals in good agreement with relevant experiment.
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Affiliation(s)
- J Buckeridge
- University College London, Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - C R A Catlow
- University College London, Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - D O Scanlon
- University College London, Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, United Kingdom and Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - T W Keal
- Scientific Computing Department, STFC, Daresbury Laboratory, Daresbury, Warrington WA4 4AD, United Kingdom
| | - P Sherwood
- Scientific Computing Department, STFC, Daresbury Laboratory, Daresbury, Warrington WA4 4AD, United Kingdom
| | - M Miskufova
- University College London, Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - A Walsh
- Centre for Sustainable Chemical Technologies and Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - S M Woodley
- University College London, Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - A A Sokol
- University College London, Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, United Kingdom
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15
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Roldan A, Hollingsworth N, Roffey A, Islam HU, Goodall JBM, Catlow CRA, Darr JA, Bras W, Sankar G, Holt KB, Hogarth G, de Leeuw NH. Bio-inspired CO2conversion by iron sulfide catalysts under sustainable conditions. Chem Commun (Camb) 2015; 51:7501-4. [DOI: 10.1039/c5cc02078f] [Citation(s) in RCA: 157] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
CO2conversion to small bio-molecules on greigite minerals under room temperature and pressure.
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Affiliation(s)
- A. Roldan
- Department of Chemistry
- University College London
- London
- UK
| | | | - A. Roffey
- Department of Chemistry
- University College London
- London
- UK
| | - H.-U. Islam
- Department of Chemistry
- University College London
- London
- UK
- European Synchrotron Radiation Facility
| | | | | | - J. A. Darr
- Department of Chemistry
- University College London
- London
- UK
| | - W. Bras
- European Synchrotron Radiation Facility
- Grenoble F38043
- France
| | - G. Sankar
- Department of Chemistry
- University College London
- London
- UK
| | - K. B. Holt
- Department of Chemistry
- University College London
- London
- UK
| | - G. Hogarth
- Department of Chemistry
- University College London
- London
- UK
| | - N. H. de Leeuw
- Department of Chemistry
- University College London
- London
- UK
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16
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O'Malley AJ, Catlow CRA. Molecular dynamics simulations of longer n-alkanes in silicalite: state-of-the-art models achieving close agreement with experiment. Phys Chem Chem Phys 2015; 17:1943-8. [DOI: 10.1039/c4cp04898a] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The diffusion of longer n-alkanes (n-C8–n-C16) in silicalite was studied using molecular dynamics simulations in the temperature range of 300–400 K. A close agreement is found with previous quasi-elastic neutron scattering studies for both calculated diffusion coefficients and activation energies.
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Affiliation(s)
- A. J. O'Malley
- University College London
- Department of Chemistry
- Materials Chemistry
- London WC1E 6BT
- UK
| | - C. R. A. Catlow
- University College London
- Department of Chemistry
- Materials Chemistry
- London WC1E 6BT
- UK
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Sokol AA, Farrow MR, Buckeridge J, Logsdail AJ, Catlow CRA, Scanlon DO, Woodley SM. Double bubbles: a new structural motif for enhanced electron-hole separation in solids. Phys Chem Chem Phys 2014; 16:21098-105. [PMID: 24969266 DOI: 10.1039/c4cp01900h] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electron-hole separation for novel composite systems comprised of secondary building units formed from different compounds is investigated with the aim of finding suitable materials for photocatalysis. Pure and mixed SOD and LTA superlattices of (ZnO)12 and (GaN)12, single-shell bubbles are constructed as well as core@shell single component frameworks composed of larger (ZnO)48 and (GaN)48 bubbles with each containing one smaller bubble. Enthalpies of formation for all systems are comparable with fullerenes. Hole and electron separation is achieved most efficiently by the edge sharing framework composed of (GaN)12@(ZnO)48 double bubbles, with the hole localised on the nitrogen within the smaller bubbles and the excited electron on zinc within the larger cages.
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Affiliation(s)
- A A Sokol
- Department of Chemistry, Kathleen Lonsdale Materials Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
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Abstract
A series of model catalytic cycles for CO2 conversion at metal oxide surface vacancy sites is presented.
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Affiliation(s)
- C. A. Downing
- Department of Chemistry
- University College London
- London WC1E 6BT, UK
| | - A. A. Sokol
- Department of Chemistry
- University College London
- London WC1E 6BT, UK
| | - C. R. A. Catlow
- Department of Chemistry
- University College London
- London WC1E 6BT, UK
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Buckeridge J, Bromley ST, Walsh A, Woodley SM, Catlow CRA, Sokol AA. One-dimensional embedded cluster approach to modeling CdS nanowires. J Chem Phys 2013; 139:124101. [DOI: 10.1063/1.4820415] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Downing CA, Ahmady B, Catlow CRA, de Leeuw NH. The interaction of hydrogen with the {010} surfaces of Mg and Fe olivine as models for interstellar dust grains: a density functional theory study. Philos Trans A Math Phys Eng Sci 2013; 371:20110592. [PMID: 23734054 PMCID: PMC3682719 DOI: 10.1098/rsta.2011.0592] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
There is no consensus as yet to account for the significant presence of water on the terrestrial planets, but suggested sources include direct hydrogen adsorption from the parent molecular cloud after the planets' formation, and delivery of hydrous material via comets or asteroids external to the zone of the terrestrial planets. Alternatively, a more recent idea is that water may have directly adsorbed onto the interstellar dust grains involved in planetary formation. In this work, we use electronic structure calculations based on the density functional theory to investigate and compare the bulk and {010} surface structures of the magnesium and iron end-members of the silicate mineral olivine, namely forsterite and fayalite, respectively. We also report our results on the adsorption of atomic hydrogen at the mineral surfaces, where our calculations show that there is no activation barrier to the adsorption of atomic hydrogen at these surfaces. Furthermore, different surface sites activate the atom to form either adsorbed hydride or proton species in the form of hydroxy groups on the same surface, which indicates that these mineral surfaces may have acted as catalytic sites in the immobilization and reaction of hydrogen atoms to form dihydrogen gas or water molecules.
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Affiliation(s)
- C A Downing
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AH, UK.
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Scanlon DO, King PDC, Singh RP, de la Torre A, Walker SM, Balakrishnan G, Baumberger F, Catlow CRA. Controlling bulk conductivity in topological insulators: key role of anti-site defects. Adv Mater 2012; 24:2154-8. [PMID: 22430985 DOI: 10.1002/adma.201200187] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Intrinsic topological insulators are realized by alloying Bi(2)Te(3) with Bi(2)Se(3). Angle-resolved photoemission and bulk transport measurements reveal that the Fermi level is readily tuned into the bulk bandgap. First-principles calculations of the native defect landscape highlight the key role of anti-site defects for achieving this, and predict optimal growth conditions to realize maximally resistive topological insulators.
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Affiliation(s)
- D O Scanlon
- University College London, Kathleen Lonsdale Materials Chemistry, Department of Chemistry, London, UK.
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Catlow CRA, Guo ZX, Miskufova M, Shevlin SA, Smith AGH, Sokol AA, Walsh A, Wilson DJ, Woodley SM. Advances in computational studies of energy materials. Philos Trans A Math Phys Eng Sci 2010; 368:3379-3456. [PMID: 20566517 DOI: 10.1098/rsta.2010.0111] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We review recent developments and applications of computational modelling techniques in the field of materials for energy technologies including hydrogen production and storage, energy storage and conversion, and light absorption and emission. In addition, we present new work on an Sn2TiO4 photocatalyst containing an Sn(II) lone pair, new interatomic potential models for SrTiO3 and GaN, an exploration of defects in the kesterite/stannite-structured solar cell absorber Cu2ZnSnS4, and report details of the incorporation of hydrogen into Ag2O and Cu2O. Special attention is paid to the modelling of nanostructured systems, including ceria (CeO2, mixed Ce(x)O(y) and Ce2O3) and group 13 sesquioxides. We consider applications based on both interatomic potential and electronic structure methodologies; and we illustrate the increasingly quantitative and predictive nature of modelling in this field.
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Affiliation(s)
- C R A Catlow
- Department of Chemistry, Materials Chemistry, 3rd Floor, Kathleen Lonsdale Building, University College London, , Gower Street, London WC1E 6BT, UK.
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Woodley SM, Watkins MB, Sokol AA, Shevlin SA, Catlow CRA. Construction of nano- and microporous frameworks from octahedral bubble clusters. Phys Chem Chem Phys 2009; 11:3176-85. [DOI: 10.1039/b902600b] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Watkins MB, Shevlin SA, Sokol AA, Slater B, Catlow CRA, Woodley SM. Bubbles and microporous frameworks of silicon carbide. Phys Chem Chem Phys 2009; 11:3186-200. [DOI: 10.1039/b902603g] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Abstract
After over a quarter of a century, the doors of the world's first synchrotron radiation source have closed. Its contribution to materials science in the past and the future should not be underestimated.
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Affiliation(s)
- G N Greaves
- Institute of Mathematics and Physics, and Centre for Advanced Functional Materials and Devices, Aberystwyth University, Aberystwyth SY23 3BZ, UK.
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Shevlin SA, Guo ZX, van Dam HJJ, Sherwood P, A. Catlow CR, Sokol AA, Woodley SM. Structure, optical properties and defects in nitride (III–V) nanoscale cage clusters. Phys Chem Chem Phys 2008; 10:1944-59. [DOI: 10.1039/b719838h] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Affiliation(s)
- R. A. Jackson
- a Department of Chemistry , University of Keele , Keele, Staffs , ST5 5BG , UK
| | - C. R. A. Catlow
- a Department of Chemistry , University of Keele , Keele, Staffs , ST5 5BG , UK
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Affiliation(s)
- C. R. A. Catlow
- a Department of Chemistry , University College London , 20 Gordon Street, London WCIH OAJ, U.K
| | - D. G. Muxworthy
- b Inorganic Chemistry Laboratory , South Parks Road, Oxford , U.K
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Corish J, Quigley JM, Jacobs PWM, Catlow CRA. A theoretical study of the aggregation of alkaline-earth cations in crystalline NaCl, KCl and KBr. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/01418618108244491] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Price SL, Hamad S, Torrisi A, Karamertzanis PG, Leslie M, Catlow CRA. Applications Of Dl_poly And Dl_multi To Organic Molecular Crystals. Molecular Simulation 2006. [DOI: 10.1080/08927020600880810] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Catlow CRA, Mackrodt WC, Norgett MJ, Stoneham AM. The basic atomic processes of corrosion II. Defect structures and cation transport in transition-metal oxides. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/01418617908243095] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Affiliation(s)
- P. Saul
- a Chemistry Department , University College London , 20 Gordon Street, London , WC1H OAJ , England
| | - C. R. A. Catlow
- a Chemistry Department , University College London , 20 Gordon Street, London , WC1H OAJ , England
| | - J. Kendrick
- b New Science Group, ICI plc, The Heath, Runcorn , Cheshire , England
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Affiliation(s)
- X. Zhang
- a Department of Physics , National University of Singapore , Lower Kent Ridge Road, Singapore , 0511
| | - C. R. A. Catlow
- b Davy Faraday Research Laboratory, The Royal Institution of Great Britain , 21 Albemarle Street, London , WlX 4BS , U.K
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Affiliation(s)
- B. Vessal
- a Department of Chemistry , University of Keele , Keele, Staffs. , ST5 5BG , UK
- b The Atlas Centre, Rutherford Appleton Laboratory , Chilton, Didcot , Oxfordshire , OX11 OQX , UK
| | - M. Amini
- c Department of Physics , Isfahan University of Technology , Isfahan , Iran
| | - M. Leslie
- d Daresbury Laboratory , Warrington , WA4 4AD , UK
| | - C. R. A. Catlow
- e The Royal Institution of Great Britain , 21 Albemarle Street, London , W1X 4BS , UK
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Affiliation(s)
- S. M. Tomlinson
- a Department of Chemistry , Keele University , Staffordshire , ST5 5BG
| | - C. R. A. Catlow
- a Department of Chemistry , Keele University , Staffordshire , ST5 5BG
| | - H. Donnerberg
- b Department of Physics , University of Osnabrück , D-4500 , Osnabruck , West Germany
| | - M. Leslie
- c SERC Daresbury Laboratory , Warrington, Cheshire , WA4 4AD
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Affiliation(s)
- A. Dietrich
- a Laboratoire de Modélisation Moléculaire , 12 rue Adalbert de Baerenfels, 68300 , Saint-Louis , Bourgfelden , France
| | - C. R. A. Catlow
- b The Royal Institution of Great Britain , 21 Albemarle Street, London , WIX4BS , UK
| | - B. Maigret
- c Laboratoire de Chimie Théorique, URA CNRS 510, Université de Nancy I , B.P. 239, 54506 , Vandœuvre , Cédex , France
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Affiliation(s)
- D. R. Collins
- a Department of Chemistry , University of Keele , Staffordshire , ST5 5BG
| | - C. R. A. Catlow
- a Department of Chemistry , University of Keele , Staffordshire , ST5 5BG
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Palin EJ, Grasa GA, Catlow CRA. A molecular mechanics investigation of the structures and energetics of two classes of Ru(II) complexes with applications in homogeneous catalysis. Molecular Simulation 2006. [DOI: 10.1080/08927020600982491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Greaves GN, Gurman SJ, Catlow CRA, Chadwick AV, Houde-Walter S, Henderson CMB, Dobson BR. A structural basis for ionic diffusion in oxide glasses. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/01418619108204878] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- G. N. Greaves
- a Daresbury Laboratory, Science and Engineering Research Council , Warrington , WA44AD , England
| | - S. J. Gurman
- b Department of Physics , University of Leicester , Leicester , LE17RH , England
| | - C. R. A. Catlow
- c Davy Faraday Research Laboratory, The Royal Institution , 21 Albemarle Street, London , W1X , England
| | - A. V. Chadwick
- d University Chemical Laboratory, University of Kent , Canterbury , CT2 7NH , England
| | - S. Houde-Walter
- e Institute of Optics, University of Rochester , New York , 14627 , USA
| | - C. M. B. Henderson
- f Department of Geology , University of Manchester , Manchester , M13 9PL , England
| | - B. R. Dobson
- a Daresbury Laboratory, Science and Engineering Research Council , Warrington , WA44AD , England
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Affiliation(s)
- C. R. A. Catlow
- a Davy Faraday Laboratory, The Royal Institution , 21 Albemarle Street, London , W1X , England
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Vessal B, Amini M, Fincham D, Catlow CRA. Water-like melting behaviour of SiO2 investigated by the molecular dynamics simulation technique. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/13642818908209741] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- B. Vessal
- a Department of Chemistry , University of Keele , Keele, Staffordshire ST5 5BG, England
- b The Atlas Centre, Rutherford Appleton Laboratory Chilton , Didcot, Oxfordshire OX11 0QX, England
| | - M. Amini
- c Department of Physics , University of Keele , Keele, Staffordshire, ST5 5BG, England
| | - D. Fincham
- d Computer Centre , University of Keele , Keele , Staffordshire , ST5 5BG , England
| | - C. R. A. Catlow
- a Department of Chemistry , University of Keele , Keele, Staffordshire ST5 5BG, England
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