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Mason DR, Nguyen-Manh D, Lindblad VW, Granberg FG, Lavrentiev MY. An empirical potential for simulating hydrogen isotope retention in highly irradiated tungsten. J Phys Condens Matter 2023; 35. [PMID: 37681432 DOI: 10.1088/1361-648x/acf25f] [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] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 08/21/2023] [Indexed: 09/09/2023]
Abstract
We describe the parameterization of a tungsten-hydrogen empirical potential designed for use with large-scale molecular dynamics simulations of highly irradiated tungsten containing hydrogen isotope atoms, and report test results. Particular attention has been paid to getting good elastic properties, including the relaxation volumes of small defect clusters, and to the interaction energy between hydrogen isotopes and typical irradiation-induced defects in tungsten. We conclude that the energy ordering of defects changes with the ratio of H atoms to point defects, indicating that this potential is suitable for exploring mechanisms of trap mutation, including vacancy loop to plate-like void transformations.
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Affiliation(s)
- Daniel R Mason
- UK Atomic Energy Authority, Culham Centre for Fusion Energy, Oxfordshire OX14 3DB, United Kingdom
| | - Duc Nguyen-Manh
- UK Atomic Energy Authority, Culham Centre for Fusion Energy, Oxfordshire OX14 3DB, United Kingdom
| | - Victor W Lindblad
- Department of Physics, University of Helsinki, PO Box 43, Helsinki FIN-00014, Finland
| | - Fredric G Granberg
- Department of Physics, University of Helsinki, PO Box 43, Helsinki FIN-00014, Finland
| | - Mikhail Yu Lavrentiev
- UK Atomic Energy Authority, Culham Centre for Fusion Energy, Oxfordshire OX14 3DB, United Kingdom
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2
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El Atwani O, Vo HT, Tunes MA, Lee C, Alvarado A, Krienke N, Poplawsky JD, Kohnert AA, Gigax J, Chen WY, Li M, Wang YQ, Wróbel JS, Nguyen-Manh D, Baldwin JKS, Tukac OU, Aydogan E, Fensin S, Martinez E. Author Correction: A quinary WTaCrVHf nanocrystalline refractory high-entropy alloy withholding extreme irradiation environments. Nat Commun 2023; 14:3490. [PMID: 37311813 DOI: 10.1038/s41467-023-39294-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023] Open
Affiliation(s)
- O El Atwani
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA.
| | - H T Vo
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - M A Tunes
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - C Lee
- Center for Integrated Nanotechnology, Los Alamos National Laboratory, Los Alamos, NM, USA
- Department of Materials and Mechanical Engineering, Auburn University, Auburn, AL, USA
| | - A Alvarado
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM, USA
- Departments of Mechanical Engineering and Materials Science and Engineering, Clemson University, Clemson, SC, USA
| | - N Krienke
- Materials Science and Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - J D Poplawsky
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - A A Kohnert
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - J Gigax
- Center for Integrated Nanotechnology, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - W-Y Chen
- Division of Nuclear Engineering, Argonne National Laboratory, Lemon, IL, USA
| | - M Li
- Division of Nuclear Engineering, Argonne National Laboratory, Lemon, IL, USA
| | - Y Q Wang
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - J S Wróbel
- Faculty of Materials Science and Engineering, Warsaw University of Technology, ul. Wołoska, 02-507, Warsaw, Poland
| | - D Nguyen-Manh
- Culham Center for Fusion Energy, United Kingdom Atomic Energy Authority, Abingdon, OX14 3DB, UK
- Department of Materials, University of Oxford, Oxford, OX1 3PH, UK
| | - J K S Baldwin
- Center for Integrated Nanotechnology, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - O U Tukac
- Metallurgical and Materials Engineering, Middle East Technical University, Ankara, Turkey
| | - E Aydogan
- Metallurgical and Materials Engineering, Middle East Technical University, Ankara, Turkey
| | - S Fensin
- Center for Integrated Nanotechnology, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - E Martinez
- Departments of Mechanical Engineering and Materials Science and Engineering, Clemson University, Clemson, SC, USA
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3
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El Atwani O, Vo HT, Tunes MA, Lee C, Alvarado A, Krienke N, Poplawsky JD, Kohnert AA, Gigax J, Chen WY, Li M, Wang YQ, Wróbel JS, Nguyen-Manh D, Baldwin JKS, Tukac OU, Aydogan E, Fensin S, Martinez E. A quinary WTaCrVHf nanocrystalline refractory high-entropy alloy withholding extreme irradiation environments. Nat Commun 2023; 14:2516. [PMID: 37130885 PMCID: PMC10154406 DOI: 10.1038/s41467-023-38000-y] [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] [Received: 09/20/2022] [Accepted: 04/10/2023] [Indexed: 05/04/2023] Open
Abstract
In the quest of new materials that can withstand severe irradiation and mechanical extremes for advanced applications (e.g. fission & fusion reactors, space applications, etc.), design, prediction and control of advanced materials beyond current material designs become paramount. Here, through a combined experimental and simulation methodology, we design a nanocrystalline refractory high entropy alloy (RHEA) system. Compositions assessed under extreme environments and in situ electron-microscopy reveal both high thermal stability and radiation resistance. We observe grain refinement under heavy ion irradiation and resistance to dual-beam irradiation and helium implantation in the form of low defect generation and evolution, as well as no detectable grain growth. The experimental and modeling results-showing a good agreement-can be applied to design and rapidly assess other alloys subjected to extreme environmental conditions.
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Affiliation(s)
- O El Atwani
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA.
| | - H T Vo
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - M A Tunes
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - C Lee
- Center for Integrated Nanotechnology, Los Alamos National Laboratory, Los Alamos, NM, USA
- Department of Materials and Mechanical Engineering, Auburn University, Montgomery, AL, USA
| | - A Alvarado
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM, USA
- Departments of Mechanical Engineering and Materials Science and Engineering, Clemson University, Clemson, SC, USA
| | - N Krienke
- Materials Science and Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - J D Poplawsky
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - A A Kohnert
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - J Gigax
- Center for Integrated Nanotechnology, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - W-Y Chen
- Division of Nuclear Engineering, Argonne National Laboratory, Lemon, IL, USA
| | - M Li
- Division of Nuclear Engineering, Argonne National Laboratory, Lemon, IL, USA
| | - Y Q Wang
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - J S Wróbel
- Faculty of Materials Science and Engineering, Warsaw University of Technology, ul. Wołoska, 02-507, Warsaw, Poland
| | - D Nguyen-Manh
- Culham Center for Fusion Energy, United Kingdom Atomic Energy Authority, Abingdon, OX14 3DB, UK
- Department of Materials, University of Oxford, Oxford, OX1 3PH, UK
| | - J K S Baldwin
- Center for Integrated Nanotechnology, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - O U Tukac
- Metallurgical and Materials Engineering, Middle East Technical University, Ankara, Turkey
| | - E Aydogan
- Metallurgical and Materials Engineering, Middle East Technical University, Ankara, Turkey
| | - S Fensin
- Center for Integrated Nanotechnology, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - E Martinez
- Departments of Mechanical Engineering and Materials Science and Engineering, Clemson University, Clemson, SC, USA
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4
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Lai HTT, Nguyen LH, Phan AD, Kranjc A, Nguyen TT, Nguyen-Manh D. A comparative study of receptor interactions between SARS-CoV and SARS-CoV-2 from molecular modeling. J Mol Model 2022; 28:305. [PMID: 36074206 PMCID: PMC9453729 DOI: 10.1007/s00894-022-05231-7] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 07/16/2022] [Indexed: 11/26/2022]
Abstract
The pandemic of COVID-19 severe acute respiratory syndrome, which was fatal for millions of people worldwide, triggered the race to understand in detail the molecular mechanisms of this disease. In this work, the differences of interactions between the SARS-CoV/SARS-CoV-2 Receptor binding domain (RBD) and the human Angiotensin Converting Enzyme 2 (ACE2) receptor were studied using in silico tools. Our results show that SARS-CoV-2 RBD is more stable and forms more interactions with ACE2 than SARS-CoV. At its interface, three stable binding patterns are observed and named red-K31, green-K353 and blue-M82 according to the central ACE2 binding residue. In SARS-CoV instead, only the first two binding patches are persistently formed during the MD simulation. Our MM/GBSA calculations indicate the binding free energy difference of about 2.5 kcal/mol between SARS-CoV-2 and SARS-CoV which is compatible with the experiments. The binding free energy decomposition points out that SARS-CoV-2 RBD–ACE2 interactions of the red-K31 (\documentclass[12pt]{minimal}
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\begin{document}$$-23.5~\pm ~0.2~kcal/mol$$\end{document}-23.5±0.2kcal/mol) and blue-M82 (\documentclass[12pt]{minimal}
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\begin{document}$$-9.1~\pm ~0.1~kcal/mol$$\end{document}-9.1±0.1kcal/mol) patterns contribute more to the binding affinity than in SARS-CoV (\documentclass[12pt]{minimal}
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\begin{document}$$-1.8~\pm ~0.02~kcal/mol$$\end{document}-1.8±0.02kcal/mol for red-K31), while the contribution of the green-K353 pattern is very similar in the two strains (\documentclass[12pt]{minimal}
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\begin{document}$$-22.7~\pm ~0.1~kcal/mol$$\end{document}-22.7±0.1kcal/mol for SARS-CoV-2 and SARS-CoV, respectively). Five groups of mutations draw our attention at the RBD–ACE2 binding interface, among them, the mutation –PPA469-471/GVEG482-485 has the most important and favorable impact on SARS-CoV-2 binding to the ACE2 receptor. These results, highlighting the molecular differences in the binding between the two viruses, contribute to the common knowledge about the new corona virus and to the development of appropriate antiviral treatments, addressing the necessity of ongoing pandemics.
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Affiliation(s)
- Hien T. T. Lai
- Key Laboratory for Multiscale Simulation of Complex Systems, VNU University of Science, Vietnam National University, 334 Nguyen Trai street, Hanoi, 11416 Vietnam
| | - Ly H. Nguyen
- Key Laboratory for Multiscale Simulation of Complex Systems, VNU University of Science, Vietnam National University, 334 Nguyen Trai street, Hanoi, 11416 Vietnam
| | - Anh D. Phan
- Faculty of Materials Science and Engineering, Phenikaa Institute for Advanced Study, Phenikaa University, Hanoi, 12116 Vietnam
| | - Agata Kranjc
- Institute of Neuroscience and Medicine (INM-9)/ Institute for Advanced Simulation (IAS-5), Forschungszentrum Jülich, Jülich, 52428 Germany
- Laboratoire de Biochimie Théorique, UPR 9080 CNRS, Université de Paris, 13 rue Pierre et Marie Curie, F-75005 Paris, France
- Institut de Biologie Physico-Chimique-Fondation Edmond de Rotschild, SL Research University, 75005 Paris, France
| | - Toan T. Nguyen
- Key Laboratory for Multiscale Simulation of Complex Systems, VNU University of Science, Vietnam National University, 334 Nguyen Trai street, Hanoi, 11416 Vietnam
| | - Duc Nguyen-Manh
- CCFE, United Kingdom Atomic Energy Authority, OX14 3DB Abingdon, UK
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5
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Lloyd MJ, Martinez E, Messina L, Nguyen-Manh D. Development of a solute and defect concentration dependant Ising model for the study of transmutation induced segregation in neutron irradiated W-(Re, Os) systems. J Phys Condens Matter 2021; 33:475902. [PMID: 34407520 DOI: 10.1088/1361-648x/ac1ec4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 08/18/2021] [Indexed: 06/13/2023]
Abstract
In this study, radiation-induced precipitation of transmutation products is addressed via the development of a new solute and vacancy concentration dependant Ising model for the W-Re-Os system. This new model includes interactions between both Os and Re atoms with vacancies, thus facilitating more representative simulations of transmutation in fusion reactor components. Local solute concentration dependencies are introduced for the W-Re, W-Os and Re-Os pair interactions. The model correctly accounts for the repulsion between small clusters of vacancies and the attraction between larger clusters/voids, via the introduction of local vacancy concentration dependant interaction coefficients between pairs of atoms and vacancies. To parameterise the pair interactions between atoms and/or vacancies, the enthalpy of mixing, ΔHmix, for various configurations and solute/defect concentrations, was calculated using density functional theory, within 6 binary systems: W-Re, W-Os, Re-Os, W-vacancy, Re-vacancy and Os-vacancy. The new energy model was implemented into the SPPARKS Monte Carlo code, and successfully used to predict the formation of voids decorated with Re and Os solute atoms. Analysis suggests that there is a strong thermodynamic tendency for Os to bind to these voids with a comparatively weaker binding from Re atoms. The binding energies of various solute/vacancy clusters were calculated and showed that Re and Os solute atoms tend to stabilise small clusters of vacancies, increasing the attractive binding energy between the constituents.
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Affiliation(s)
- M J Lloyd
- Department of Materials, University of Oxford, Parks Road, Oxford, OX13PH, United Kingdom
- United Kingdom Atomic Energy Authority, Culham Science Centre, Abingdon, Oxfordshire, OX143DB, United Kingdom
| | - E Martinez
- Department of Mechanical Engineering, Clemson University, Clemson, SC 29634, United States of America
- Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634, United States of America
| | - L Messina
- CEA, DEs, IRESNE, DEC-Service d'Études et de Simulation du Comportement des Combustibles, Cadarache F-13108 Saint-Paul-Lez-Durance, France
| | - D Nguyen-Manh
- Department of Materials, University of Oxford, Parks Road, Oxford, OX13PH, United Kingdom
- United Kingdom Atomic Energy Authority, Culham Science Centre, Abingdon, Oxfordshire, OX143DB, United Kingdom
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Fernández-Caballero A, Bousser E, Shubeita S, Wady P, Gu Y, Krishna R, Gorley M, Nguyen-Manh D, Mummery P, Pickering E. High-dose ion irradiation damage in Fe28Ni28Mn26Cr18 characterised by TEM and depth-sensing nanoindentation. Nuclear Materials and Energy 2021. [DOI: 10.1016/j.nme.2021.101028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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7
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Dang DTX, Hoang HT, Doan TLH, Thoai N, Kawazoe Y, Nguyen-Manh D. Effect of axial molecules and linker length on CO 2 adsorption and selectivity of CAU-8: a combined DFT and GCMC simulation study. RSC Adv 2021; 11:12460-12469. [PMID: 35423819 PMCID: PMC8697253 DOI: 10.1039/d0ra10121d] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 03/19/2021] [Indexed: 11/30/2022] Open
Abstract
Density Functional Theory (DFT) and Grand Canonical Monte Carlo (GCMC) calculations are performed to study the structures and carbon dioxide (CO2) adsorption properties of the newly designed metal–organic framework based on the CAU-8 (CAU stands for Christian-Albrechts Universität) prototype. In the new MOFs, the 4,4′-benzophenonedicarboxylic acid (H2BPDC) linker of CAU-8 is substituted by 4,4′-oxalylbis(azanediyl)dibenzoic acid (H2ODA) and 4,4′-teraphthaloylbis(azanediyl)dibenzoic acid (H2TDA) containing amide groups (–CO–NH- motif). Furthermore, MgO6 octahedral chains where dimethyl sulfoxide (DMSO) decorating the axial position bridged two Mg2+ ions are considered. The formation energies indicate that modified CAU-8 is thermodynamically stable. The reaction mechanisms between the metal clusters and the linkers to form the materials are also proposed. GCMC calculations show that CO2 adsorptions and selectivities of Al-based MOFs are better than those of Mg-based MOFs, which is due to DMSO. Amide groups made CO2 molecules more intensively distributed besides organic linkers. CO2 uptakes and selectivities of MOFs containing H2TDA linkers are better in comparison with those of MOFs containing H2BPDC linkers or H2ODA linkers. Density Functional Theory (DFT) and Grand Canonical Monte Carlo (GCMC) calculations are performed to study the structures and CO2 adsorption properties of the newly designed metal–organic framework based on the CAU-8 prototype.![]()
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Affiliation(s)
- Diem Thi-Xuan Dang
- Center for Innovative Materials and Architectures (INOMAR)
- Ho Chi Minh City 721337
- Vietnam
- Vietnam National University – Ho Chi Minh City
- Ho Chi Minh City 721337
| | - Hieu Trung Hoang
- Center for Innovative Materials and Architectures (INOMAR)
- Ho Chi Minh City 721337
- Vietnam
- Vietnam National University – Ho Chi Minh City
- Ho Chi Minh City 721337
| | - Tan Le Hoang Doan
- Center for Innovative Materials and Architectures (INOMAR)
- Ho Chi Minh City 721337
- Vietnam
- Vietnam National University – Ho Chi Minh City
- Ho Chi Minh City 721337
| | - Nam Thoai
- Vietnam National University – Ho Chi Minh City
- Ho Chi Minh City 721337
- Vietnam
- High Performance Computing Lab
- Faculty of Computer Science & Engineering
| | - Yoshiyuki Kawazoe
- New Industry Creation Hatchery Center
- Tohoku University
- Sendai 980-8579
- Japan
- Department of Physics
| | - Duc Nguyen-Manh
- CCFE
- United Kingdom Atomic Energy Authority
- Culham Science Centre
- UK
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Sobieraj D, Wróbel JS, Rygier T, Kurzydłowski KJ, El Atwani O, Devaraj A, Martinez Saez E, Nguyen-Manh D. Chemical short-range order in derivative Cr-Ta-Ti-V-W high entropy alloys from the first-principles thermodynamic study. Phys Chem Chem Phys 2020; 22:23929-23951. [PMID: 33073813 DOI: 10.1039/d0cp03764h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [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 development of high-entropy alloys (HEAs) focuses on exploring compositional regions in multi-component systems with all alloy elements in equal or near-equal atomic concentrations. Initially it was based on the main idea that high mixing configurational entropy contributions to the alloy free energy could promote the formation of a single solid solution phase. By using the ab-initio based Cluster Expansion (CE) Hamiltonian model constructed for the quinary bcc Cr-Ta-Ti-V-W system in combination with Monte Carlo (MC) simulations, we show that the phase stability and chemical short-range order (SRO) of the equiatomic quinary and five sub-quaternary systems, as well as their derivative alloys, can dramatically change the order-disorder transition temperatures (ODTT) as a function of alloy compositions. In particular, it has been found, that the equiatomic quaternary Ta-Ti-V-W and Cr-Ta-Ti-W alloys had the lowest order-disorder transition temperature (500 K) among all the analysed equiatomic compositions. In all investigated alloy systems, the strongest chemical ordering has been observed between Cr and V, which led to the conclusion that decreasing the concentration of either Cr or V might be beneficial in terms of decreasing the ODTT. It also predicts that increasing concentration of Ti significantly decreases the ODTT. Our analysis of chemical SRO as a function of alloy composition allows to understand the microstructure evolution of HEAs as a function of temperature in excellent agreement with available experimental observations. Importantly, our free energy of mixing and SRO calculations predict that the origin of precipitates formed by Cr- and V-rich in the sub-quaternary Cr-Ta-V-W system is driven by the thermodynamics. The modelling results are in an excellent agreement with experimental observation of Cr and V segregation in the W0.38Ta0.36Cr0.15V0.11 alloy which in turns shows an exceptional radiation resistance.
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Affiliation(s)
- Damian Sobieraj
- Faculty of Materials Science and Engineering, Warsaw University of Technology, ul. Wołoska 141, 02-507 Warsaw, Poland. and CCFE, United Kingdom Atomic Energy Authority, Abingdon OX14 3DB, UK.
| | - Jan S Wróbel
- Faculty of Materials Science and Engineering, Warsaw University of Technology, ul. Wołoska 141, 02-507 Warsaw, Poland.
| | - Tomasz Rygier
- Faculty of Materials Science and Engineering, Warsaw University of Technology, ul. Wołoska 141, 02-507 Warsaw, Poland.
| | - Krzysztof J Kurzydłowski
- Faculty of Mechanical Engineering, Białystok University of Technology, ul. Wiejska 45C, 15-351 Białystok, Poland
| | | | - Arun Devaraj
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, 902 Battelle Blvd, Richland, WA 99354, USA
| | | | - Duc Nguyen-Manh
- CCFE, United Kingdom Atomic Energy Authority, Abingdon OX14 3DB, UK. and Department of Materials, University of Oxford, Oxford OX1 3PH, UK
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9
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Litnovsky A, Schmitz J, Klein F, De Lannoye K, Weckauf S, Kreter A, Rasinski M, Coenen JW, Linsmeier C, Gonzalez-Julian J, Bram M, Povstugar I, Morgan T, Nguyen-Manh D, Gilbert M, Sobieraj D, Wróbel JS. Smart Tungsten-based Alloys for a First Wall of DEMO. Fusion Engineering and Design 2020. [DOI: 10.1016/j.fusengdes.2020.111742] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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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10
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Arakawa K, Marinica MC, Fitzgerald S, Proville L, Nguyen-Manh D, Dudarev SL, Ma PW, Swinburne TD, Goryaeva AM, Yamada T, Amino T, Arai S, Yamamoto Y, Higuchi K, Tanaka N, Yasuda H, Yasuda T, Mori H. Quantum de-trapping and transport of heavy defects in tungsten. Nat Mater 2020; 19:508-511. [PMID: 31988514 DOI: 10.1038/s41563-019-0584-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 12/11/2019] [Indexed: 06/10/2023]
Abstract
The diffusion of defects in crystalline materials1 controls macroscopic behaviour of a wide range of processes, including alloying, precipitation, phase transformation and creep2. In real materials, intrinsic defects are unavoidably bound to static trapping centres such as impurity atoms, meaning that their diffusion is dominated by de-trapping processes. It is generally believed that de-trapping occurs only by thermal activation. Here, we report the direct observation of the quantum de-trapping of defects below around one-third of the Debye temperature. We successfully monitored the de-trapping and migration of self-interstitial atom clusters, strongly trapped by impurity atoms in tungsten, by triggering de-trapping out of equilibrium at cryogenic temperatures, using high-energy electron irradiation and in situ transmission electron microscopy. The quantum-assisted de-trapping leads to low-temperature diffusion rates orders of magnitude higher than a naive classical estimate suggests. Our analysis shows that this phenomenon is generic to any crystalline material.
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Affiliation(s)
- Kazuto Arakawa
- Next Generation TATARA Co-Creation Centre, Organization for Industrial Innovation, Shimane University, Matsue, Japan.
| | - Mihai-Cosmin Marinica
- DEN-Service de Recherches de Métallurgie Physique, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | | | - Laurent Proville
- DEN-Service de Recherches de Métallurgie Physique, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Duc Nguyen-Manh
- CCFE, United Kingdom Atomic Energy Authority, Culham Science Centre, Abingdon, Oxfordshire, UK
| | - Sergei L Dudarev
- CCFE, United Kingdom Atomic Energy Authority, Culham Science Centre, Abingdon, Oxfordshire, UK
| | - Pui-Wai Ma
- CCFE, United Kingdom Atomic Energy Authority, Culham Science Centre, Abingdon, Oxfordshire, UK
| | | | - Alexandra M Goryaeva
- DEN-Service de Recherches de Métallurgie Physique, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Tetsuya Yamada
- Railway, Automotive & Machinery Parts Unit, Osaka Steel Works, Nippon Steel Corporation, Osaka, Japan
| | - Takafumi Amino
- Advanced Technology Research Laboratories, Nippon Steel Corporation, Amagasaki, Japan
| | - Shigeo Arai
- Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Japan
| | - Yuta Yamamoto
- Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Japan
| | - Kimitaka Higuchi
- Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Japan
| | - Nobuo Tanaka
- Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Japan
| | - Hidehiro Yasuda
- Research Centre for Ultra-High Voltage Electron Microscopy, Osaka University, Ibaraki, Osaka, Japan
| | - Tetsuya Yasuda
- Research Centre for Ultra-High Voltage Electron Microscopy, Osaka University, Ibaraki, Osaka, Japan
| | - Hirotaro Mori
- Research Centre for Ultra-High Voltage Electron Microscopy, Osaka University, Ibaraki, Osaka, Japan
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Dang DTX, Dong HC, Kawazoe Y, Kuo JL, Nguyen-Manh D. The electronic structures and magnetic properties of mixed-valence Fe-based metal–organic VNU-15 frameworks: a theoretical study from linear response DFT+U calculations. RSC Adv 2020; 10:34690-34701. [PMID: 35514422 PMCID: PMC9056818 DOI: 10.1039/d0ra05865c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 09/02/2020] [Indexed: 02/03/2023] Open
Abstract
The crystal symmetries, electronic structures, and magnetic properties of metal–organic VNU-15 frameworks (VNU = Vietnam National University) were investigated using density functional calculations (DFT) with an on-site Coulomb repulsion approximation, Ueff, of 4.30 eV, determined via the linear response method. Two different orientations of dimethylammonium (DMA+) cations in VNU-15 were investigated. Antiferromagnetic configurations were predicted to be the ground states, with Fe ions in high-spin states for both phases. Furthermore, VNU-15 had intrinsic semiconductor electronic behavior with a small band gap of about 1.20 eV. The change in the orientation of DMA+ led to changes in the dispersion of the band structure, the band gap, and the Fe contributions to the valence band and conduction band. A fascinating feature was found involving exchange of oxidation numbers between two adjacent Fe atoms in the two phases. Our results revealed that VNU-15 has strong oxidation activity and predicted the important role of an anisotropic effect on the hole and electron effective masses. The findings presented that the electronic and magnetic properties could be controlled via hydrogen bonds and proved VNU-15 to be a prospective material for photocatalytic applications. The effects of DMA+ cation orientation on the electronic structures and magnetic properties of the metal–organic framework VNU-15 are investigated, and VNU-15 is proved to be a prospective material for photocatalytic applications.![]()
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Affiliation(s)
- Diem Thi-Xuan Dang
- Center for Innovative Materials and Architectures (INOMAR)
- Ho Chi Minh City 721337
- Vietnam
- Vietnam National University – Ho Chi Minh City
- Ho Chi Minh City 721337
| | - Hieu Cao Dong
- Center for Innovative Materials and Architectures (INOMAR)
- Ho Chi Minh City 721337
- Vietnam
- Vietnam National University – Ho Chi Minh City
- Ho Chi Minh City 721337
| | - Yoshiyuki Kawazoe
- New Industry Creation Hatchery Center
- Tohoku University
- Sendai 980-8579
- Japan
- Department of Physics
| | - Jer-Lai Kuo
- Institute of Atomic and Molecular Sciences
- Academia Sinica
- Taipei 10617
- Taiwan
| | - Duc Nguyen-Manh
- CCFE
- United Kingdom Atomic Energy Authority
- Culham Science Centre
- UK
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12
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Nguyen-Thuy T, Le-Hoang P, Hoang Vu N, Le TNM, Le Hoang Doan T, Kuo JL, Nguyen TT, Phan TB, Nguyen-Manh D. Hydrogen adsorption mechanism of MOF-74 metal–organic frameworks: an insight from first principles calculations. RSC Adv 2020; 10:43940-43949. [PMID: 35517181 PMCID: PMC9058421 DOI: 10.1039/d0ra08864a] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Accepted: 11/24/2020] [Indexed: 12/17/2022] Open
Abstract
The microscopic mechanism of the H2 adsorption of two Mg-MOF-74 isoreticular frameworks, one with a benzenedicarboxylate (BDC) linker and the other with a dihydroxyfumarate (DHF) linker, were studied on the basis of density functional theory (DFT) method. Possible adsorption sites on the internal surface of the two MOFs were detected using ab initio molecular dynamics (AIMD) annealing simulations. The simulations were able to reproduce all adsorption sites which have been experimentally observed for the BDC-based M-MOF-74 frameworks with M = Ni and Zn. In descending order of binding strengths, they are the adsorption sites primarily induced by the open metal sites P1, the oxygen atoms of the oxido groups P2 and the aromatic rings P3. The H2–framework binding strengths were properly evaluated by taking into account the vibrational zero-point energy (ZPE) contribution. An additional type of adsorption sites induced by the oxygen atoms of the carboxyl groups P4 is predicted for the Mg-MOF-74 framework. Two types of adsorption sites primarily induced by the open metal sites P1 and oxygen atoms of the carboxyl groups P2 were predicted for the DHF-based Mg-MOF-74 framework. Detailed analysis of the electron density showed that the electrostatic interaction of the H2 molecule with the charge distribution of the local framework environment within a radius of ∼3.5 Å is a key factor to define adsorption positions and binding strength. The absence of the P4 sites in the BDC-based Zn-MOF-74 framework is caused by the lower charge density at the oxygen atoms induced by less electro-positive metal. The substitution of the nonaromatic DHF linker for the aromatic BDC linker reduces the binding strength at the metal induced adsorption sites by 1.45 kJ mol−1 due to the absence of the aromatic ring. The microscopic mechanism of the H2 adsorption of two Mg-MOF-74 isoreticular frameworks, one with a benzenedicarboxylate linker and the other with a dihydroxyfumarate linker, were studied on the basis of density functional theory (DFT) method.![]()
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Affiliation(s)
- Trang Nguyen-Thuy
- Key Laboratory for Multiscale Simulation of Complex Systems
- University of Science
- Vietnam National University – Hanoi
- Hanoi
- Vietnam
| | - Phong Le-Hoang
- Key Laboratory for Multiscale Simulation of Complex Systems
- University of Science
- Vietnam National University – Hanoi
- Hanoi
- Vietnam
| | - Nam Hoang Vu
- Vietnam National University
- HoChiMinh City
- Vietnam
- Faculty of Materials Science and Technology
- University of Science
| | - Thong Nguyen-Minh Le
- Institute of Atomic and Molecular Sciences
- Academia Sinica
- Taipei City 10617
- Taiwan
- Molecular Science and Technology Program
| | - Tan Le Hoang Doan
- Center for Innovative Materials and Architectures
- Vietnam National University Ho Chi Minh City
- Ho Chi Minh City
- Vietnam
| | - Jer-Lai Kuo
- Institute of Atomic and Molecular Sciences
- Academia Sinica
- Taipei City 10617
- Taiwan
| | - Toan T. Nguyen
- Key Laboratory for Multiscale Simulation of Complex Systems
- University of Science
- Vietnam National University – Hanoi
- Hanoi
- Vietnam
| | - Thang Bach Phan
- Center for Innovative Materials and Architectures
- Vietnam National University Ho Chi Minh City
- Ho Chi Minh City
- Vietnam
- Vietnam National University
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13
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Dang DTX, Nguyen HTD, Thoai N, Kuo JL, Nguyen NTT, Nguyen-Manh D. Mechano-chemical stability and water effect on gas selectivity in mixed-metal zeolitic imidazolate frameworks: a systematic investigation from van der Waals corrected density functional theory. Phys Chem Chem Phys 2020; 22:1598-1610. [DOI: 10.1039/c9cp04199k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A series of Zn/Cu Zeolitic Imidazolate Frameworks (ZIFs) ZIF-202, -203, and -204 are systematically investigated by Density Functional Theory (DFT) with and without van der Waals (vdW) corrections.
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Affiliation(s)
- Diem Thi-Xuan Dang
- Center for Innovative Materials and Architectures (INOMAR)
- Vietnam National University – Ho Chi Minh City
- Ho Chi Minh City 721337
- Vietnam
| | - Huong Thi-Diem Nguyen
- Faculty of Chemistry
- University of Science
- Vietnam National University – Ho Chi Minh City
- Ho Chi Minh City 721337
- Vietnam
| | - Nam Thoai
- High Performance Computing Lab and Faculty of Computer Science & Engineering
- University of Technology
- Vietnam National University – Ho Chi Minh City
- Ho Chi Minh City 721337
- Vietnam
| | - Jer-Lai Kuo
- Institute of Atomic and Molecular Sciences
- Academia Sinica
- Taipei 10617
- Taiwan
| | | | - Duc Nguyen-Manh
- Culham Center for Fusion Energy
- United Kingdom Atomic Energy Authority
- UK
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El-Atwani O, Li N, Li M, Devaraj A, Baldwin JKS, Schneider MM, Sobieraj D, Wróbel JS, Nguyen-Manh D, Maloy SA, Martinez E. Outstanding radiation resistance of tungsten-based high-entropy alloys. Sci Adv 2019; 5:eaav2002. [PMID: 30838329 PMCID: PMC6397024 DOI: 10.1126/sciadv.aav2002] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 01/23/2019] [Indexed: 05/07/2023]
Abstract
A body-centered cubic W-based refractory high entropy alloy with outstanding radiation resistance has been developed. The alloy was grown as thin films showing a bimodal grain size distribution in the nanocrystalline and ultrafine regimes and a unique 4-nm lamella-like structure revealed by atom probe tomography (APT). Transmission electron microscopy (TEM) and x-ray diffraction show certain black spots appearing after thermal annealing at elevated temperatures. TEM and APT analysis correlated the black spots with second-phase particles rich in Cr and V. No sign of irradiation-created dislocation loops, even after 8 dpa, was observed. Furthermore, nanomechanical testing shows a large hardness of 14 GPa in the as-deposited samples, with near negligible irradiation hardening. Theoretical modeling combining ab initio and Monte Carlo techniques predicts the formation of Cr- and V-rich second-phase particles and points at equal mobilities of point defects as the origin of the exceptional radiation tolerance.
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Affiliation(s)
- O. El-Atwani
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
- Corresponding author. (O.E.); (E.M.)
| | - N. Li
- Center for Integrated Nanotechnologies, MPA-CINT, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - M. Li
- Division of Nuclear Engineering, Argonne National Laboratory, Argonne, IL, USA
| | - A. Devaraj
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - J. K. S. Baldwin
- Center for Integrated Nanotechnologies, MPA-CINT, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - M. M. Schneider
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - D. Sobieraj
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Ulica Wołoska 141, 02-507 Warsaw, Poland
| | - J. S. Wróbel
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Ulica Wołoska 141, 02-507 Warsaw, Poland
| | - D. Nguyen-Manh
- Department of Materials Science and Scientific Computing, CCFE, United Kingdom Atomic Energy Authority, Abingdon, Oxfordshire OX14 3DB, UK
| | - S. A. Maloy
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - E. Martinez
- Theoretical Division, T-1, Los Alamos National Laboratory, Los Alamos, NM, USA
- Corresponding author. (O.E.); (E.M.)
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15
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Fernández-Caballero A, Fedorov M, Wróbel JS, Mummery PM, Nguyen-Manh D. Configurational Entropy in Multicomponent Alloys: Matrix Formulation from Ab Initio Based Hamiltonian and Application to the FCC Cr-Fe-Mn-Ni System. Entropy (Basel) 2019; 21:e21010068. [PMID: 33266784 PMCID: PMC7514176 DOI: 10.3390/e21010068] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 01/10/2019] [Accepted: 01/11/2019] [Indexed: 11/16/2022]
Abstract
Configuration entropy is believed to stabilize disordered solid solution phases in multicomponent systems at elevated temperatures over intermetallic compounds by lowering the Gibbs free energy. Traditionally, the increment of configuration entropy with temperature was computed by time-consuming thermodynamic integration methods. In this work, a new formalism based on a hybrid combination of the Cluster Expansion (CE) Hamiltonian and Monte Carlo simulations is developed to predict the configuration entropy as a function of temperature from multi-body cluster probability in a multi-component system with arbitrary average composition. The multi-body probabilities are worked out by explicit inversion and direct product of a matrix formulation within orthonomal sets of point functions in the clusters obtained from symmetry independent correlation functions. The matrix quantities are determined from semi canonical Monte Carlo simulations with Effective Cluster Interactions (ECIs) derived from Density Functional Theory (DFT) calculations. The formalism is applied to analyze the 4-body cluster probabilities for the quaternary system Cr-Fe-Mn-Ni as a function of temperature and alloy concentration. It is shown that, for two specific compositions (Cr 25Fe 25Mn 25Ni 25 and Cr 18Fe 27Mn 27Ni 28), the high value of probabilities for Cr-Fe-Fe-Fe and Mn-Mn-Ni-Ni are strongly correlated with the presence of the ordered phases L1 2 -CrFe 3 and L1 0-MnNi, respectively. These results are in an excellent agreement with predictions of these ground state structures by ab initio calculations. The general formalism is used to investigate the configuration entropy as a function of temperature and for 285 different alloy compositions. It is found that our matrix formulation of cluster probabilities provides an efficient tool to compute configuration entropy in multi-component alloys in a comparison with the result obtained by the thermodynamic integration method. At high temperatures, it is shown that many-body cluster correlations still play an important role in understanding the configuration entropy before reaching the solid solution limit of high-entroy alloys (HEAs).
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Affiliation(s)
- Antonio Fernández-Caballero
- School of Mechanical Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK
- CCFE, United Kingdom Atomic Energy Authority, Abingdon OX14 3DB, UK
| | - Mark Fedorov
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Woloska 141, 02-507 Warsaw, Poland
| | - Jan S. Wróbel
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Woloska 141, 02-507 Warsaw, Poland
| | - Paul M. Mummery
- School of Mechanical Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK
| | - Duc Nguyen-Manh
- CCFE, United Kingdom Atomic Energy Authority, Abingdon OX14 3DB, UK
- Correspondence:
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16
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Pham HQ, Le DQ, Pham-Tran NN, Kawazoe Y, Nguyen-Manh D. Electron delocalization in single-layer phthalocyanine-based covalent organic frameworks: a first principle study. RSC Adv 2019; 9:29440-29447. [PMID: 35528447 PMCID: PMC9071832 DOI: 10.1039/c9ra05159g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 09/12/2019] [Indexed: 11/21/2022] Open
Abstract
In this work, we first investigate the localized electronic states in the band structures of three single-layer COFs based on typical building units of COFs chemistry. Our results confirm that the polar nature of strong bonds in these building units is a hindrance to a fully delocalized structure and disfavors the band-like mechanism of transport. We then show that a rational design of the building units can lead to dispersive band states in the electronic structure and results in conducting single-layer COFs. We demonstrate this strategy by investigating the charge carrier transport in a series of single-layer Ni-phthalocyanine (NiPc) covalent organic frameworks (COFs), namely, NiPc-P, NiPc-2P, and NiPc-3P. Three proposed COFs exhibit semiconducting band gaps ranging from 0.55 to 0.91 eV. Their room-temperature intrinsic mobility is predicted to be in range of 200–600 cm2 V−1 s−1 and 20 000–60 000 cm2 V−1 s−1 for electrons and holes, respectively, which are comparable to those of phosphorene and higher than those of the trigonal prismatic molybdenum disulfide. NiPc are dynamically and mechanically stable and can be synthesized via the co-evaporation between Ni and corresponding tetracyano linkers. Importantly, we demonstrate that the properties of the single-layer COFs can be tuned by engineering the organic building blocks. Our theoretical study not only provides insight into the design principles for semiconducting single-layer COFs but also highlights the significance of reticular chemistry in the development of a new generation of two-dimensional materials for optoelectronic applications. A series of single-layer phthalocyanine-based covalent-organic frameworks (COFs) are shown to possess tunable delocalized electronic states which are attractive for optoelectronic applications.![]()
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Affiliation(s)
- Hung Q. Pham
- Faculty of Chemistry
- University of Science
- VNU-HCM
- Ho Chi Minh City
- Vietnam
| | - Dong Q. Le
- Faculty of Chemistry
- University of Science
- VNU-HCM
- Ho Chi Minh City
- Vietnam
| | | | - Yoshiyuki Kawazoe
- New Industry Creation Hatchery Centre
- Tohoku University
- Sendai
- Japan
- SRM Institute of Science and Technology
| | - Duc Nguyen-Manh
- Culham Centre for Fusion Energy
- Culham Science Centre
- Abingdon
- UK
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17
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Abstract
We present an empirical interatomic potential for tungsten, particularly well suited for simulations of vacancy-type defects. We compare energies and structures of vacancy clusters generated with the empirical potential with an extensive new database of values computed using density functional theory, and show that the new potential predicts low-energy defect structures and formation energies with high accuracy. A significant difference to other popular embedded-atom empirical potentials for tungsten is the correct prediction of surface energies. Interstitial properties and short-range pairwise behaviour remain similar to the Ackford-Thetford potential on which it is based, making this potential well-suited to simulations of microstructural evolution following irradiation damage cascades. Using atomistic kinetic Monte Carlo simulations, we predict vacancy cluster dissociation in the range 1100-1300 K, the temperature range generally associated with stage IV recovery.
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Affiliation(s)
- D R Mason
- CCFE, Culham Centre for Fusion Energy, Abingdon, Oxfordshire OX14 3DB, United Kingdom
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18
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Wróbel JS, Nguyen-Manh D, Kurzydłowski KJ, Dudarev SL. A first-principles model for anomalous segregation in dilute ternary tungsten-rhenium-vacancy alloys. J Phys Condens Matter 2017; 29:145403. [PMID: 28177296 DOI: 10.1088/1361-648x/aa5f37] [Citation(s) in RCA: 4] [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: 06/06/2023]
Abstract
The occurrence of segregation in dilute alloys under irradiation is a highly unusual phenomenon that has recently attracted attention, stimulated by the interest in the fundamental properties of alloys as well as by their applications. The fact that solute atoms segregate in alloys that, according to equilibrium thermodynamics, should exhibit full solubility, has significant practical implications, as the formation of precipitates strongly affects physical and mechanical properties of alloys. A lattice Hamiltonian, generalizing the so-called 'ABV' Ising model and including collective many-body inter-atomic interactions, has been developed to treat rhenium solute atoms and vacancies in tungsten as components of a ternary alloy. The phase stability of W-Re-vacancy alloys is assessed using a combination of density functional theory (DFT) calculations and cluster expansion (CE) simulations. The accuracy of CE parametrization is evaluated against the DFT data, and the cross-validation error is found to be less than 4.2 meV/atom. The free energy of W-Re-vacancy ternary alloys is computed as a function of temperature using quasi-canonical Monte Carlo simulations, using effective two, three and four-body interactions. In the low rhenium concentration range (<5 at.[Formula: see text]Re), solute segregation is found to occur in the form of voids decorated by Re atoms. These vacancy-rhenium clusters remain stable over a broad temperature range from 800 K to 1600 K. At lower temperatures, simulations predict the formation of Re-rich rhenium-vacancy clusters taking the form of sponge-like configurations that contain from 30 to 50 at.[Formula: see text]Re. The anomalous vacancy-mediated segregation of Re atoms in W can be rationalized by analyzing binding energy dependence as a function of Re to vacancy ratio as well as chemical Re-W and Re-vacancy interactions and short-range order parameters. DFT calculations show that rhenium-vacancy binding energies can be as high as 1.5 eV if the rhenium/vacancy ratio is in the range from 2.4 to 6.6. The predicted Re clustering agrees with experimental observations of precipitation in self-ion irradiated W-2[Formula: see text] Re alloys and neutron-irradiated alloys containing 1.4 at.[Formula: see text]Re.
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Affiliation(s)
- J S Wróbel
- CCFE, UK Atomic Energy Authority, Culham Science Centre, Abingdon, Oxon OX14 3DB, United Kingdom. Faculty of Materials Science and Engineering, Warsaw University of Technology, Wołoska 141, 02-507 Warsaw, Poland
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Leong Z, Wróbel JS, Dudarev SL, Goodall R, Todd I, Nguyen-Manh D. The Effect of Electronic Structure on the Phases Present in High Entropy Alloys. Sci Rep 2017; 7:39803. [PMID: 28059106 PMCID: PMC5216361 DOI: 10.1038/srep39803] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 11/18/2016] [Indexed: 11/23/2022] Open
Abstract
Multicomponent systems, termed High Entropy Alloys (HEAs), with predominantly single solid solution phases are a current area of focus in alloy development. Although different empirical rules have been introduced to understand phase formation and determine what the dominant phases may be in these systems, experimental investigation has revealed that in many cases their structure is not a single solid solution phase, and that the rules may not accurately distinguish the stability of the phase boundaries. Here, a combined modelling and experimental approach that looks into the electronic structure is proposed to improve accuracy of the predictions of the majority phase. To do this, the Rigid Band model is generalised for magnetic systems in prediction of the majority phase most likely to be found. Good agreement is found when the predictions are confronted with data from experiments, including a new magnetic HEA system (CoFeNiV). This also includes predicting the structural transition with varying levels of constituent elements, as a function of the valence electron concentration, n, obtained from the integrated spin-polarised density of states. This method is suitable as a new predictive technique to identify compositions for further screening, in particular for magnetic HEAs.
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Affiliation(s)
- Zhaoyuan Leong
- Department of Materials Science &Engineering, University of Sheffield, Sheffield, UK
| | - Jan S Wróbel
- CCFE, Culham Science Centre for Fusion Energy, Culham, Abingdon, OX14 3DB, Oxfordshire, UK.,Faculty of Materials Science and Engineering, Warsaw University of Technology, ul. Wołoska 141, 02-507 Warszawa, Poland
| | - Sergei L Dudarev
- CCFE, Culham Science Centre for Fusion Energy, Culham, Abingdon, OX14 3DB, Oxfordshire, UK
| | - Russell Goodall
- Department of Materials Science &Engineering, University of Sheffield, Sheffield, UK
| | - Iain Todd
- Department of Materials Science &Engineering, University of Sheffield, Sheffield, UK
| | - Duc Nguyen-Manh
- CCFE, Culham Science Centre for Fusion Energy, Culham, Abingdon, OX14 3DB, Oxfordshire, UK
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Le HM, Bui VQ, Hoang Tran P, Pham-Tran NN, Kawazoe Y, Nguyen-Manh D. The prospect of sensitizing organic dyes attached to the MoS2 surface: Physical insights from density functional theory investigations. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2016.11.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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Le HM, Pham TT, Dinh TS, Kawazoe Y, Nguyen-Manh D. First-principles modeling of 3d-transition-metal-atom adsorption on silicene: a linear-response DFT + U approach. J Phys Condens Matter 2016; 28:135301. [PMID: 26940978 DOI: 10.1088/0953-8984/28/13/135301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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
By employing DFT + U calculations with the linear response method, we investigate the interactions between various 3d transition-metal atoms (Cr, Mn, Fe, Co) and silicene. In the cases of two-dimensional (2D) FeSi2 and CoSi2, the metal atoms tend to penetrate into the silicene layer. While CoSi2 is non-magnetic, FeSi2 exhibits a total magnetic moment of 2.21 μ(B)/cell. Upon the examination of 2D MSi6, a trend in anti-ferromagnetic (AFM) favorability in the z-direction is observed according to our DFT + U calculations. In the ferromagnetic (FM) states (less stable), each primary unit cell of CrSi6, MnSi6, and FeSi6 possesses different levels of total magnetization (4.01, 5.18, and 2.00 μ B/cell, respectively). The absolute magnetization given by AFM MSi6 structures varies in the range of 5.33-5.84 μ(B)/cell. A direct band gap in AFM MnSi6 (0.2 eV) is predicted, while the metastable FM FeSi6 structure has a wider band gap (0.85 eV). Interestingly, there are superexchange interactions between metal atoms in the MSi6 systems, which result in the AFM alignments.
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Affiliation(s)
- Hung M Le
- Department of Materials Science, University of Science, Vietnam National University, Ho Chi Minh City, Vietnam
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23
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Lavrentiev MY, Wróbel JS, Nguyen-Manh D, Dudarev SL. Magnetic and thermodynamic properties of face-centered cubic Fe–Ni alloys. Phys Chem Chem Phys 2014; 16:16049-59. [PMID: 24964377 DOI: 10.1039/c4cp01366b] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Le HM, Hirao H, Kawazoe Y, Nguyen-Manh D. First-principles modeling of C60–Cr–graphene nanostructures for supporting metal clusters. Phys Chem Chem Phys 2013; 15:19395-404. [DOI: 10.1039/c3cp53529k] [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: 11/21/2022]
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25
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Vu NH, Le HV, Cao TM, Pham VV, Le HM, Nguyen-Manh D. Anatase-rutile phase transformation of titanium dioxide bulk material: a DFT + U approach. J Phys Condens Matter 2012; 24:405501. [PMID: 22951569 DOI: 10.1088/0953-8984/24/40/405501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The anatase-rutile phase transformation of TiO(2) bulk material is investigated using a density functional theory (DFT) approach in this study. According to the calculations employing the Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional with the Vanderbilt ultrasoft pseudopotential, it is suggested that the anatase phase is more energetically stable than rutile, which is in variance with the experimental observations. Consequently, the DFT + U method is employed in order to predict the correct structural stability in titania from electronic-structure-based total energy calculations. The Hubbard U term is determined by examining the band structure of rutile with various values of U from 3 to 10 eV. At U = 5 eV, a theoretical bandgap for rutile is obtained as 3.12 eV, which is in very good agreement with the reported experimental bandgap. Hence, we choose the DFT + U method (with U = 5 eV) to investigate the transformation pathway using the newly-developed solid-state nudged elastic band (ss-NEB) method, and consequently obtain an intermediate transition structure that is 9.794 eV per four-TiO(2) above the anatase phase. When the Ti-O bonds in the transition state are examined using charge density analysis, seven Ti-O bonds (out of 24 bonds in the anatase unit cell) are broken, and this result is in excellent agreement with a previous experimental study (Penn and Banfield 1999 Am. Miner. 84 871-6).
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Affiliation(s)
- Nam H Vu
- Faculty of Materials Science, University of Science, Vietnam National University, Ho Chi Minh City, Vietnam
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Lavrentiev MY, Mergia K, Gjoka M, Nguyen-Manh D, Apostolopoulos G, Dudarev SL. Magnetic cluster expansion simulation and experimental study of high temperature magnetic properties of Fe-Cr alloys. J Phys Condens Matter 2012; 24:326001-5. [PMID: 22785126 DOI: 10.1088/0953-8984/24/32/326001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We present a combined experimental and computational study of high temperature magnetic properties of Fe-Cr alloys with chromium content up to about 20 at.%. The magnetic cluster expansion method is applied to model the magnetic properties of random Fe-Cr alloys, and in particular the Curie transition temperature, as a function of alloy composition. We find that at low (3-6 at.%) Cr content the Curie temperature increases with the increase of Cr concentration. It is maximum at approximately 6 at.% Cr and then decreases for higher Cr content. The same feature is found in thermo-magnetic measurements performed on model Fe-Cr alloys, where a 5 at.% Cr alloy has a higher Curie temperature than pure Fe. The Curie temperatures of 10 and 15 at.% Cr alloys are found to be lower than the Curie temperature of pure Fe.
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Affiliation(s)
- M Yu Lavrentiev
- EURATOM/CCFE Fusion Association, Culham Centre for Fusion Energy, Abingdon, Oxfordshire OX14 3DB, UK
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Abstract
We present a magnetic bond-order potential (BOP) that is able to provide a correct description of both directional covalent bonds and magnetic interactions in iron. This potential, based on the tight binding approximation and the Stoner model of itinerant magnetism, forms a direct bridge between the electronic-structure and the atomistic modeling hierarchies. Even though BOP calculations are computationally more demanding than those using common empirical potentials, the formalism can be used for studies of complex defect configurations in large atomic ensembles exceeding 10(5) atoms. Our studies of dislocations in α-Fe demonstrate that correct descriptions of directional covalent bonds and magnetism are crucial for a reliable modeling of these defects.
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Affiliation(s)
- M Mrovec
- IAM, Karlsruhe Institute of Technology, Karlsruhe, Germany.
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Mrovec M, Vitek V, Nguyen-Manh D, Pettifor DG, Wang LG, Sob M. Study of the Mechanical Behavior of BCC Transition Metals Using Bond-Order Potentials. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-578-199] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractDeformation properties of body-centered-cubic transition metals are controlled by the core structure of screw dislocations and their studies involve extensive computer simulations. In this paper we present the recently constructed bond-order potentials (BOP) that are based on the realspace parametrized tight-binding method. In order to examine the applicability of the potentials we have evaluated the energy differences of alternative structures, investigated several transformation paths leading to large distortions and calculated phonon dispersions. Using these potentials we have calculated γ-surfaces that relate to the dislocation core structures and discuss then the importance of directional bonding in studies of dislocations in transition metals.
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Nguyen-Manh D, Tsymbal E, Pettifor DG, Arcangeli C, Tank R, Andersen OK, Pasturel A. Spin-Polarized Density of States and Electron Tunnelling from the CO/Al2O3 Interface. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-492-319] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTIn order to elucidate the mechanism of spin-polarized electron tunneling in thin-film ferromagnet-insulator junctions, self-consistent band structure calculations of the CO/Al2O3 interface have been performed using a new LMTO technique. Since the results of the calculations are very sensitive to the distance between the Co and Al planes, we have minimised the total energy with respect to this distance. Our calculations show that at the Fermi energy a strong bonding between the 3d-electrons of Co with the sp-electrons of Al at the interface can have an important influence on the spin polarization of the layer-projected density of states (LPDOS) of inner Al and O layers. Since the Fermi energy lies within the minority-spin d-band of Co but above the majority-spin d-band, the sp-d bonding results in a smaller LPDOS of the minority-spin electrons of the interfacial Al layers in comparison to that of the majority-spin electrons. This asymmetry in the LPDOS extends to the inner Al2O3 layers implying a positive spin polarization of the tunneling density of states. The result is consistent with experimental observations on tunnelling from cobalt through alumina where positive values of the spin polarization of the tunnelling current were measured.
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Nguyen-Manh D, Pettifor DG, Sithole HM, Ngoepe PE, Arcangeli C, Tank R, Jepsen O. Electronic Structure, Pressure Dependence and Optical Properties of FeS2. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-491-401] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTA revisited electronic structure study of iron pyrite, FeS2, has been performed using a new Tight-Binding Linear Muffin-Tin Orbital (TB-LMTO) technique in which the radii of overlapping MT spheres are determined from a full potential construction. The interstitial spheres were chosen to provide an efficient packing of space while ensuring that the overlap between the spheres remain small. We have found that this treatment of interstitial spheres results in a dramatic improvement in the description of the electronic structure and the binding energy curves for FeS2 in comparison with a previous LMTO calculation. In particular, the energy band gap, the equilibrium lattice constant and the bulk modulus are all in much better agreement with experimental observations. Moreover, the calculated equation of state is in excellent accord with recent measured P- V data up to pressures of 15GPa with overall deviations of less than 10%. The predicted reflectivity spectrum of FeS2 as a function of pressure gives the observed behaviour of the optical edge. The bonding behaviour the orthorhombic marcasite phase of FeS2 is also discussed within this new TB-LMTO formalism.
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Abstract
We present the first derivation of the analytic expression for the Peierls-Nabarro potential for crowdion migration using the double sine-Gordon model. The analysis is guided by the group-specific trend in the shapes of the periodic lattice potentials calculated for the body-centered-cubic transition metals in groups 5B and 6B of the periodic table. We combine density-functional calculations of the crowdion's profile and environment with an extended version of the analytical Frenkel-Kontorova model, and determine the effective potential experienced by the defect's center of mass. This reveals important underlying differences between the metals in these groups, which are inaccessible to either the numerical or analytical approaches alone, and accounts for the previously unexplained significantly higher crowdion migration temperatures observed in the metals of group 6B relative to those of group 5B.
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Affiliation(s)
- S P Fitzgerald
- EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB, United Kingdom
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Abstract
Electron energy loss spectra are simulated for a C70 crystalline structure. It is found that the simulated spectrum is similar to the unoccupied density of states of a C70 molecule, indicating that the crystalline structure has only a small effect on the spectrum. Unlike the case of a single molecule, however, the main contribution to the second peak in the spectrum cannot be ascribed as being due to the equatorial atoms.
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Affiliation(s)
- R J Nicholls
- Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK.
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Abstract
Iridium is unique among the face-centered cubic metals in that it undergoes brittle cleavage after a period of plastic deformation under tensile stress. Atomistic simulation using a quantum-mechanically derived bond-order potential shows that in iridium, two core structures for the screw dislocation are possible: a glissile planar core and a metastable nonplanar core. Transformation between the two core structures is athermal and leads to exceptionally high rates of cross slip during plastic deformation. Associated with this athermal cross slip is an exponential increase in the dislocation density and strong work hardening from which brittle cleavage is a natural consequence.
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Affiliation(s)
- Marc J Cawkwell
- Department of Materials Science and Engineering, University of Pennsylvania, 3231 Walnut Street, Philadelphia, PA 19104-6202, USA.
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Lee S, Nicholls R, Nguyen-Manh D, Pettifor D, Briggs G, Lazar S, Pankhurst D, Cockayne D. Electron energy loss spectra of C60 and C70 fullerenes. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.01.089] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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McBride W, Cockayne DJH, Nguyen-Manh D. Electron diffraction from nanovolumes of amorphous material using coherent convergent illumination. Ultramicroscopy 2003; 96:191-200. [PMID: 12672570 DOI: 10.1016/s0304-3991(03)00007-x] [Citation(s) in RCA: 16] [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: 10/27/2022]
Abstract
Using a conventional transmission electron microscope that incorporates a field emission gun it is possible to focus an electron beam to form a small probe (<1nm full-width at half-maximum). Such a probe can then be used to perform high spatial resolution diffraction experiments. The high spatial resolution allows technologically interesting amorphous volumes, such as those found in glassy intergranular phases or in semiconductor implantations, to be investigated directly. In order to achieve the probe characteristics necessary to investigate nanovolumes of material the probe must be highly convergent which results in it being highly coherent. In this paper we examine the effect of coherent convergent illumination on electron diffraction data taken from nanovolumes of amorphous material. It is shown that, for amorphous volumes as small as 1.2nm in diameter, the additional interference effects induced in the diffraction data by the use of coherent convergent illumination are largely suppressed by the lack of order in amorphous materials. This allows the use of deconvolution techniques, developed for the correction of broadening of the diffraction pattern in the case of incoherent illumination, and the subsequent application of reduced density function (G(r)) analysis, to also be used for coherent illumination.
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Affiliation(s)
- W McBride
- Department of Materials, University of Oxford, USA.
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Nguyen-Manh D, Mayou D, Morgan GJ, Pasturel A. The Hall coefficient and the derivative of the density of states in amorphous metals. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0305-4608/17/4/025] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Nguyen-Manh D, Pettifor DG, Vitek V. Analytic environment-dependent tight-binding bond integrals: application to MoSi2. Phys Rev Lett 2000; 85:4136-4139. [PMID: 11056643 DOI: 10.1103/physrevlett.85.4136] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2000] [Indexed: 05/23/2023]
Abstract
We present the first derivation of explicit analytic expressions for the environmental dependence of the sigma, pi, and delta bond integrals within the orthogonal two-center tight-binding approximation by using the recently developed bond-order potential theory to invert the nonorthogonality matrix. We illustrate the power of this new formalism by showing that it not only captures the transferability of the bond integrals between elemental bcc Mo and Si and binary C11(b) MoSi2 but also predicts the absence of any discontinuity between first and second nearest neighbors for the ddsigma bond integral even though large discontinuities exist for ppsigma, pppi, and ddpi.
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Affiliation(s)
- D Nguyen-Manh
- Department of Materials, University of Oxford, Oxford, Parks Road, OX1 3PH, United Kingdom
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Nguyen-Manh D, Ntoahae PS, Pettifor DG, Ngoepe PE. Electronic Structure of Platinum-Group Minerals: Prediction of Semiconductor Band Gaps. Molecular Simulation 1999. [DOI: 10.1080/08927029908022083] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [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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Sithole HM, Nguyen-Manh D, Pettifor DG, Ngoepe PE. Internal Relaxation, Band Gaps and Elastic Constant Calculations of FeS2. Molecular Simulation 1999. [DOI: 10.1080/08927029908022084] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [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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Mayou D, Nguyen-Manh D, Pasturel A, Cyrot-Lackmann F. Model for the hybridization effect in disordered systems. Phys Rev B Condens Matter 1986; 33:3384-3391. [PMID: 9938718 DOI: 10.1103/physrevb.33.3384] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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