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Yang X, Guo P, Hu S, Gao Z, Yao W, Cheng J, Poncé S, Wang B, Ren W. Ab initio study of temperature-dependent piezoelectric and electronic properties of thermally stable GaPO 4. Phys Chem Chem Phys 2024; 26:21530-21537. [PMID: 39082083 DOI: 10.1039/d4cp02270j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2024]
Abstract
Gallium-phosphate (GaPO4) is one of the ultra-high thermally stable piezoelectric materials with a high critical temperature of 1206 K. Here, first principles calculations with quasi-harmonic approximation are performed to study thermal and other physical properties of α-GaPO4. For the electronic structure, we focus on the electron-phonon interaction and lattice expansion effects on the temperature-dependent band gap, which plays a significant role in zero-point renormalization. Significantly, the large piezoelectric constants e11 primarily comes from intrinsic sensitivity of Ga and O sites to axial strain, while P atoms contribute little, which remains true in other quartz-like type APO4 (A = B, Al, In). Our work provides an insight into the temperature-dependent electronic and piezoelectric properties of α-GaPO4 and motivates its applications in a high temperature environment.
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Affiliation(s)
- Xiaoqing Yang
- School of Physics and National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China
- Physics Department, Materials Genome Institute, State Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of High Temperature Superconductors, International Centre for Quantum and Molecular Structures, Shanghai University, Shanghai 200444, China.
| | - Pan Guo
- Physics Department, Materials Genome Institute, State Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of High Temperature Superconductors, International Centre for Quantum and Molecular Structures, Shanghai University, Shanghai 200444, China.
| | - Shunbo Hu
- Physics Department, Materials Genome Institute, State Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of High Temperature Superconductors, International Centre for Quantum and Molecular Structures, Shanghai University, Shanghai 200444, China.
| | - Zhibin Gao
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China
| | - Wenliang Yao
- Physics Department, Materials Genome Institute, State Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of High Temperature Superconductors, International Centre for Quantum and Molecular Structures, Shanghai University, Shanghai 200444, China.
| | - Jinrong Cheng
- Physics Department, Materials Genome Institute, State Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of High Temperature Superconductors, International Centre for Quantum and Molecular Structures, Shanghai University, Shanghai 200444, China.
| | - Samuel Poncé
- European Theoretical Spectroscopy Facility, Institute of Condensed Matter and Nanosciences, Université Catholique de Louvain, Chemin des Étoiles 8, B-1348 Louvain-la-Neuve, Belgium
- WEL Research Institute, avenue Pasteur, 6, 1300 Wavre, Belgium
| | - Baigeng Wang
- School of Physics and National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China
| | - Wei Ren
- Physics Department, Materials Genome Institute, State Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of High Temperature Superconductors, International Centre for Quantum and Molecular Structures, Shanghai University, Shanghai 200444, China.
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Sarkar A, Cerasoli FT, Viswanathan G, Donadio D, Kovnir K. ABa 6Cu 31Te 22 ( A = K, Rb, Cs) Featuring Polyanionic Copper-Telluride Frameworks with Ultralow Thermal Conductivity. ACS APPLIED MATERIALS & INTERFACES 2024; 16:39613-39622. [PMID: 39012841 DOI: 10.1021/acsami.4c06694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
Three polyanionic tellurides, ABa6Cu31Te22 (A = K, Rb, Cs), were synthesized in salt flux. The isostructural tellurides crystallize in a new structure type, in the cubic Pa3 space group with a Wyckoff sequence of d10c2b1 and large unit cell volumes of over 5500 Å3. The structures feature a framework of [CuTe4] tetrahedra and [CuTe3] trigonal pyramids with disorder in the Cu sites. The polyanionic frameworks have large square antiprism and cuboctahedral voids where Ba and alkali metal cations are situated, forming [BaTe8] and [ATe12], respectively. The overall compositions are close to being charge balanced. The large [ATe12] cuboctahedra allowed for significant anisotropic displacement of the A cations, as observed from both single crystal X-ray diffraction and heat capacity studies. Alkali cations rattling together with Cu atom displacement and disorder leads to the dispersion of phonons, thus softening the lattice and subsequently reducing the thermal conductivity. Evaluations of the electronic band structure revealed the occurrence of a narrow bandgap together with the presence of a flat band near the valence band maximum, giving rise to the high thermopower. The Cs and Rb analogues show a slope change in the temperature dependence of electrical resistivity around room temperature, which is typical for semimetals or degenerate semiconductors. For the as-synthesized and unoptimized materials, high values of the thermoelectric figure-of-merit of ∼0.2 were observed at 623 K.
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Affiliation(s)
- Arka Sarkar
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
- Ames National Laboratory, U.S. Department of Energy, Ames, Iowa 50011, United States
| | - Frank T Cerasoli
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Gayatri Viswanathan
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
- Ames National Laboratory, U.S. Department of Energy, Ames, Iowa 50011, United States
| | - Davide Donadio
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Kirill Kovnir
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
- Ames National Laboratory, U.S. Department of Energy, Ames, Iowa 50011, United States
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3
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Cheng G, Gong XG, Yin WJ. An approach for full space inverse materials design by combining universal machine learning potential, universal property model, and optimization algorithm. Sci Bull (Beijing) 2024:S2095-9273(24)00494-8. [PMID: 39142945 DOI: 10.1016/j.scib.2024.07.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Revised: 05/12/2024] [Accepted: 06/03/2024] [Indexed: 08/16/2024]
Abstract
We present a full space inverse materials design (FSIMD) approach that fully automates the materials design for target physical properties without the need to provide the atomic composition, chemical stoichiometry, and crystal structure in advance. Here, we used density functional theory reference data to train a universal machine learning potential (UPot) and transfer learning to train a universal bulk modulus model (UBmod). Both UPot and UBmod were able to cover materials systems composed of any element among 42 elements. Interfaced with optimization algorithm and enhanced sampling, the FSIMD approach is applied to find the materials with the largest cohesive energy and the largest bulk modulus, respectively. NaCl-type ZrC was found to be the material with the largest cohesive energy. For bulk modulus, diamond was identified to have the largest value. The FSIMD approach is also applied to design materials with other multi-objective properties with accuracy limited principally by the amount, reliability, and diversity of the training data. The FSIMD approach provides a new way for inverse materials design with other functional properties for practical applications.
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Affiliation(s)
- Guanjian Cheng
- College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), and Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies, Soochow University, Suzhou 215006, China; Shanghai Qi Zhi Institute, Shanghai 200232, China
| | - Xin-Gao Gong
- Key Laboratory for Computational Physical Sciences (MOE), Institute of Computational Physical Sciences, Fudan University, Shanghai 200438, China; Shanghai Qi Zhi Institute, Shanghai 200232, China
| | - Wan-Jian Yin
- College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), and Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies, Soochow University, Suzhou 215006, China; Shanghai Qi Zhi Institute, Shanghai 200232, China.
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4
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Banerjee P, Prakapenka VB, Chariton S, Shevchenko EV. Compressibility Studies of Copper Selenides Obtained by Cation Exchange Reaction Revealing the New CsCl Phase. NANO LETTERS 2024; 24:6981-6989. [PMID: 38814739 DOI: 10.1021/acs.nanolett.4c01285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
In this study, we conducted a high-pressure investigation of Cu2-xSe nanostructures with pyramid- and plate-like morphologies, created through cation exchange from zinc-blende CdSe nanocrystals and wurtzite CdSe nanoplatelets respectively. Using a diamond anvil cell setup at the APS synchrotron, we observed the phase transitions in the Cu2-xSe nanostructures up to 40 GPa, identifying a novel CsCl-type lattice with Pm3̅m symmetry above 4 GPa. This CsCl-type structure, previously unreported in copper selenides, was partially retained after decompression. Our results indicate that the initial crystalline structure of CdSe does not affect the stability of Cu2-xSe nanostructures formed via cation exchange. Both morphologies of Cu2-xSe sintered under compression, potentially contributing to the stabilization of the high-pressure phase through interfacial defects. These findings are significant for discovering new phases with potential applications in future technologies.
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Affiliation(s)
- Progna Banerjee
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Vitali B Prakapenka
- Center for Advanced Radiation Sources, The University of Chicago, Chicago, Illinois 60637, United States
| | - Stella Chariton
- Center for Advanced Radiation Sources, The University of Chicago, Chicago, Illinois 60637, United States
| | - Elena V Shevchenko
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, United States
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5
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Chanyshev A, Martirosyan N, Wang L, Chakraborti A, Purevjav N, Wang F, Kim EJ, Tang H, Fedotenko T, Bhat S, Farla R, Katsura T. Thermal Equation of State of Cubic Silicon Carbide at High Pressures. Chemphyschem 2024; 25:e202300604. [PMID: 38426668 DOI: 10.1002/cphc.202300604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 02/16/2024] [Indexed: 03/02/2024]
Abstract
We have performed in situ X-ray diffraction measurements of cubic silicon carbide (SiC) with a zinc-blende crystal structure (B3) at high pressures and temperatures using multi-anvil apparatus. The ambient volume inferred from the compression curves is smaller than that of the starting material. Using the 3rd-order Birch-Murnaghan equation of state and the Mie-Grüneisen-Debye model, we have determined the thermoelastic parameters of the B3-SiC to be K0=228±3 GPa, K0',=4.4±0.4, q=0.27±0.37, where K0, K0' and q are the isothermal bulk modulus, its pressure derivative and logarithmic volume dependence of the Grüneisen parameter, respectively. Using the 3rd-order Birch-Murnaghan EOS with the thermal expansion coefficient, the thermoelastic parameters have been found as K0=221±3 GPa, K0',=5.2±0.4, α0=0.90±0.02 ⋅ 10-5 ⋅ K-1, where α0 is the thermal expansion coefficient at room pressure and temperature. We have determined that paired B3-SiC - MgO calibrants can be used to estimate pressure and temperature simultaneously in ultrahigh-pressure experiments up to 60 GPa.
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Affiliation(s)
- Artem Chanyshev
- Bayerisches Geoinstitut, University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, German
| | - Naira Martirosyan
- Bayerisches Geoinstitut, University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, German
| | - Lin Wang
- Bayerisches Geoinstitut, University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, German
| | - Amrita Chakraborti
- Bayerisches Geoinstitut, University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, German
| | - Narangoo Purevjav
- Bayerisches Geoinstitut, University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, German
| | - Fei Wang
- Bayerisches Geoinstitut, University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, German
| | - Eun Jeong Kim
- Bayerisches Geoinstitut, University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, German
| | - Hu Tang
- Bayerisches Geoinstitut, University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, German
| | - Timofey Fedotenko
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Shrikant Bhat
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Robert Farla
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Tomoo Katsura
- Bayerisches Geoinstitut, University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, German
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6
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Manfro JFB, Rech GL, Zorzi JE, Perottoni CA. Relativistic effects and pressure-induced phase transition in CsAu. Phys Chem Chem Phys 2024; 26:5529-5536. [PMID: 38284136 DOI: 10.1039/d3cp03716a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2024]
Abstract
Cesium auride (CsAu) is an intriguing compound formed by two metals that, upon reacting, exhibits properties of an ionic salt. In this study, we employ computer simulations to explore the influence of relativistic effects on the structure and some physical properties of CsAu, as well as on a potential pressure-induced structural phase transition, the effect of high pressures on its electronic gap, and the possible transition to a conducting state. We have found that including relativistic effects reduces the lattice parameter of CsAu and brings its volumetric properties closer to the trend observed in alkali halides. It also enhances the charge transfer from cesium to gold, resulting in a difference of up to 0.15e, at ambient pressure, between non-relativistic and fully relativistic calculations. Additionally, upon increasing pressure, in the absence of intervening structural phase transitions, the closing of CsAu's band gap is expected at approximately 31.5 GPa. The inclusion of relativistic effects stabilizes the CsAu Pm3̄m structure and shifts the transition pressure to a possible high-pressure P4/mmm phase from 2 GPa (non-relativistic calculation) to 14 GPa (fully-relativistic calculation). Both the Pm3̄m and P4/mmm structures become dynamically unstable around 15 GPa, thus suggesting that the tetragonal structure may be an intermediate state towards a truly stable high-pressure CsAu phase.
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Affiliation(s)
- Júlia F B Manfro
- Universidade de Caxias do Sul, 95070-560, Caxias do Sul, RS, Brazil.
| | - Giovani L Rech
- Universidade de Caxias do Sul, 95070-560, Caxias do Sul, RS, Brazil.
| | - Janete E Zorzi
- Universidade de Caxias do Sul, 95070-560, Caxias do Sul, RS, Brazil.
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7
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Richard P, Castellano A, Béjaud R, Baguet L, Bouchet J, Geneste G, Bottin F. Ab Initio Phase Diagram of Gold in Extreme Conditions. PHYSICAL REVIEW LETTERS 2023; 131:206101. [PMID: 38039479 DOI: 10.1103/physrevlett.131.206101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/03/2023] [Accepted: 10/12/2023] [Indexed: 12/03/2023]
Abstract
A phase diagram of gold is proposed in the [0; 1000] GPa and [0; 10 000] K ranges of pressure and temperature, respectively, topologically modified with respect to previous predictions. Using finite-temperature ab initio simulations and nonequilibirum thermodynamic integration, both accelerated by machine learning, we evaluate the Gibbs free energies of three solid phases previously proposed. At room temperature, the face-centered cubic (fcc) phase is stable up to ∼500 GPa whereas the body-centered cubic (bcc) phase only appears above 1 TPa. At higher temperature, we do not highlight any fcc-bcc transition line between 200 and 400 GPa, in agreement with ramp-compressed experiments. The present results only disclose a bcc domain around 140-235 GPa and 6000-8000 K, consistent with the triple point recently found in shock experiments. We demonstrate that this re-stabilization of the bcc phase at high temperature is due to anharmonic effects.
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Affiliation(s)
- P Richard
- CEA, DAM, DIF, F-91297 Arpajon, France
- Université Paris-Saclay, CEA, Laboratoires des Matériaux en Conditions Extrêmes, 91680 Bruyères-le-Châtel, France
| | - A Castellano
- NanoMat/Q-Mat/CESAM and European Theoretical Spectroscopy Facility, Université de Liège (B5), B-4000 Liège, Belgium
| | - R Béjaud
- CEA, DAM, DIF, F-91297 Arpajon, France
- Université Paris-Saclay, CEA, Laboratoires des Matériaux en Conditions Extrêmes, 91680 Bruyères-le-Châtel, France
| | - L Baguet
- CEA, DAM, DIF, F-91297 Arpajon, France
- Université Paris-Saclay, CEA, Laboratoires des Matériaux en Conditions Extrêmes, 91680 Bruyères-le-Châtel, France
| | - J Bouchet
- CEA, DES, IRESNE, DEC F-13108 Saint-Paul-Lez-Durance, France
| | - G Geneste
- CEA, DAM, DIF, F-91297 Arpajon, France
- Université Paris-Saclay, CEA, Laboratoires des Matériaux en Conditions Extrêmes, 91680 Bruyères-le-Châtel, France
| | - F Bottin
- CEA, DAM, DIF, F-91297 Arpajon, France
- Université Paris-Saclay, CEA, Laboratoires des Matériaux en Conditions Extrêmes, 91680 Bruyères-le-Châtel, France
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8
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Jafari Daghalian Sofla S, Servio P, Rey AD. Atomistic-geometry inspired structure-composition-property relations of hydrogen sII hydrates. Sci Rep 2023; 13:19675. [PMID: 37951989 PMCID: PMC10640630 DOI: 10.1038/s41598-023-46716-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 11/03/2023] [Indexed: 11/14/2023] Open
Abstract
Gas hydrates are crystalline inclusion compounds formed by trapping gas molecules inside water cages at high pressures and low temperatures. Hydrates are promising materials for hydrogen storage, but their potential depends on understanding their mechanical properties. This work integrates density functional theory (DFT) simulations with a geometry-inspired composite material model to explore the bulk moduli of structure II hydrogen hydrates subjected to pressure loads of - 0.2 to 3 GPa, representative of the hydrogen hydrate formation conditions. Our findings reveal that structure II hydrate comprises a bi-continuous composite of small and large cages with nearly equal volume fractions. The bulk modulus increases with rising pressure but decreases with increasing composition. Notably, these results align closely with the ideal laws of mixtures, especially at low pressures and compositions, where cage interactions are minimal. This integrated DFT-laws of mixtures methodology provides a key database for fast estimation of hydrate mechanical properties without costly computations.
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Affiliation(s)
| | - Phillip Servio
- Department of Chemical Engineering, McGill University, Montreal, QC, H3A 0C5, Canada
| | - Alejandro D Rey
- Department of Chemical Engineering, McGill University, Montreal, QC, H3A 0C5, Canada.
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9
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Langer MF, Frank JT, Knoop F. Stress and heat flux via automatic differentiation. J Chem Phys 2023; 159:174105. [PMID: 37921248 DOI: 10.1063/5.0155760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 09/25/2023] [Indexed: 11/04/2023] Open
Abstract
Machine-learning potentials provide computationally efficient and accurate approximations of the Born-Oppenheimer potential energy surface. This potential determines many materials properties and simulation techniques usually require its gradients, in particular forces and stress for molecular dynamics, and heat flux for thermal transport properties. Recently developed potentials feature high body order and can include equivariant semi-local interactions through message-passing mechanisms. Due to their complex functional forms, they rely on automatic differentiation (AD), overcoming the need for manual implementations or finite-difference schemes to evaluate gradients. This study discusses how to use AD to efficiently obtain forces, stress, and heat flux for such potentials, and provides a model-independent implementation. The method is tested on the Lennard-Jones potential, and then applied to predict cohesive properties and thermal conductivity of tin selenide using an equivariant message-passing neural network potential.
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Affiliation(s)
- Marcel F Langer
- Machine Learning Group, Technische Universität Berlin, 10587 Berlin, Germany
- BIFOLD-Berlin Institute for the Foundations of Learning and Data, Berlin, Germany
- The NOMAD Laboratory at the Fritz Haber Institute of the Max Planck Society and Humboldt University, Berlin, Germany
| | - J Thorben Frank
- Machine Learning Group, Technische Universität Berlin, 10587 Berlin, Germany
- BIFOLD-Berlin Institute for the Foundations of Learning and Data, Berlin, Germany
| | - Florian Knoop
- Theoretical Physics Division, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden
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10
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Creating superconductivity in WB 2 through pressure-induced metastable planar defects. Nat Commun 2022; 13:7901. [PMID: 36550110 PMCID: PMC9780245 DOI: 10.1038/s41467-022-35191-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 11/18/2022] [Indexed: 12/24/2022] Open
Abstract
High-pressure electrical resistivity measurements reveal that the mechanical deformation of ultra-hard WB2 during compression induces superconductivity above 50 GPa with a maximum superconducting critical temperature, Tcof 17 K at 91 GPa. Upon further compression up to 187 GPa, the Tcgradually decreases. Theoretical calculations show that electron-phonon mediated superconductivity originates from the formation of metastable stacking faults and twin boundaries that exhibit a local structure resembling MgB2 (hP3, space group 191, prototype AlB2). Synchrotron x-ray diffraction measurements up to 145 GPa show that the ambient pressure hP12 structure (space group 194, prototype WB2) continues to persist to this pressure, consistent with the formation of the planar defects above 50 GPa. The abrupt appearance of superconductivity under pressure does not coincide with a structural transition but instead with the formation and percolation of mechanically-induced stacking faults and twin boundaries. The results identify an alternate route for designing superconducting materials.
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Gendron F, Cliche N, Amadon B. Role of pressure on electronic, magnetic and structural properties at iron's Curie temperature: a DFT + DMFT study. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:464003. [PMID: 36067782 DOI: 10.1088/1361-648x/ac8fd0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 09/06/2022] [Indexed: 06/15/2023]
Abstract
We use the combination of density functional theory and dynamical mean-field theory to compute the Curie temperature of the iron body-centered cubicαphase and probe its pressure dependence. Our calculations reveal thatTCshows a decrease which is very weak over a domain of pressures that is much larger than the stability domain of theαphase. This is consistent with the experimental results. We highlight the importance of the Hund's couplingJnot only on the electronic and magnetic properties but also on the structural properties. Lastly, we analyze the electronic and magnetic properties under pressure and discuss the evolution of magnetic moments in both phases in relation to the change of Curie temperature.
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Affiliation(s)
- F Gendron
- CEA, DAM, DIF, F-91297 Arpajon, France
- Université Paris-Saclay, CEA, Laboratoire Matière en Conditions Extrêmes, 91680 Bruyères-le-Châtel, France
| | - N Cliche
- CEA, DAM, DIF, F-91297 Arpajon, France
| | - B Amadon
- CEA, DAM, DIF, F-91297 Arpajon, France
- Université Paris-Saclay, CEA, Laboratoire Matière en Conditions Extrêmes, 91680 Bruyères-le-Châtel, France
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12
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Eryigit S, Parlak C, Eryigit R. γ- αphase transition of elemental cerium metal. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:295402. [PMID: 35504277 DOI: 10.1088/1361-648x/ac6c6b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 05/03/2022] [Indexed: 06/14/2023]
Abstract
The isostructuralγ-αphase transition in elemental cerium has been the subject of many experimental and theoretical studies over almost the past century without a universally agreed upon mechanism. Here, we report the results of an extensive study of electronic and magnetic structures,f-electron number, entanglement entropy, and elastic properties of cerium in the GGA +Uframework. We have found that almost all changes in the studied quantities mimic their behavior in the phase transition and could be related to the symmetry of the 4foccupation and the small change in HubbardUnear a critical value.
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Affiliation(s)
- Serpil Eryigit
- Department of Physics, Bolu Abant Izzet Baysal University, Bolu, Turkey
| | - Cihan Parlak
- Department of Physics, Bolu Abant Izzet Baysal University, Bolu, Turkey
| | - Resul Eryigit
- Department of Physics, Bolu Abant Izzet Baysal University, Bolu, Turkey
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13
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Zhang XP, Gu ZW, Xiao ZQ, Tan FL, Ye XQ, Tong YJ, Tang XS, Zhou ZY, Cheng C, Zhao J, Luo BQ, Li JM, Kuang XW, Zhao JH, Sun CW, Liu CL. Quasi-isentropic compression of LiH above 400 GPa using magnetocumulative generator. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2022; 93:043906. [PMID: 35489900 DOI: 10.1063/5.0078422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 04/06/2022] [Indexed: 06/14/2023]
Abstract
The knowledge of high-pressure behavior of LiH is significant for the validation of fundamental theoretical models and applications in thermonuclear materials and potential energy supplies. The compressibility of 7LiH under isentropic compression at high pressure was investigated experimentally and theoretically. The experimental technique for quasi-isentropic compression with low-density materials was developed using the magnetocumulative generator CJ-100 and x-ray flash radiography. The x-ray images and extracted interface of the sample target in dynamic flash radiography experiments were obtained. According to each interface size of the target both before and after compression, the compression ratio of 7LiH and reference material aluminum was obtained. The density of the reference and using its known isentropic curve provide the pressure in the reference. The pressure in 7LiH was deduced from the pressure in the reference and using the calculated gradient correction factor. The quasi-isentropic data point at 438 GPa was obtained experimentally. A semiempirical three-term complete equation of state was constructed and validated for 7LiH using the theory of Mie-Grüneisen-Debye with experimental data from the literature. The quasi-isentrope data point is reasonably consistent with the theoretical results. The quasi-isentropic experimental techniques and results broaden the existing research scope and are practical and helpful to further validate theoretical models in the future.
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Affiliation(s)
- X P Zhang
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - Z W Gu
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - Z Q Xiao
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - F L Tan
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - X Q Ye
- Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang 621907, China
| | - Y J Tong
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - X S Tang
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - Z Y Zhou
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - C Cheng
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - J Zhao
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - B Q Luo
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - J M Li
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - X W Kuang
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - J H Zhao
- Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900, China
| | - C W Sun
- Shanghai Institute of Laser Plasma, China Academy of Engineering Physics, Shanghai 201800, China
| | - C L Liu
- China Academy of Engineering Physics, Mianyang 621999, China
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14
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Luo D, Yin K, Dronskowski R. Existence of BeCN 2 and Its First-Principles Phase Diagram: Be and C Introducing Structural Diversity. J Am Chem Soc 2022; 144:5155-5162. [DOI: 10.1021/jacs.2c00592] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Dongbao Luo
- Chair of Solid-State and Quantum Chemistry, Institute of Inorganic Chemistry, RWTH Aachen University, 52056 Aachen, Germany
- Hoffmann Institute of Advanced Materials, Shenzhen Polytechnic, Liuxian Blvd, Nanshan District, 518055 Shenzhen, China
| | - Ketao Yin
- School of Physics and Electronic Engineering, Linyi University, 276005 Linyi, China
| | - Richard Dronskowski
- Chair of Solid-State and Quantum Chemistry, Institute of Inorganic Chemistry, RWTH Aachen University, 52056 Aachen, Germany
- Hoffmann Institute of Advanced Materials, Shenzhen Polytechnic, Liuxian Blvd, Nanshan District, 518055 Shenzhen, China
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15
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Ulian G, Valdrè G. QUANTAS: a Python software for the analysis of thermodynamics and elastic behavior of solids from ab initio quantum mechanical simulations and experimental data. J Appl Crystallogr 2022; 55:386-396. [PMID: 35497653 PMCID: PMC8985604 DOI: 10.1107/s1600576722000085] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 01/03/2022] [Indexed: 11/25/2022] Open
Abstract
This paper presents QUANTAS, an open-source Python-based software aimed at providing a fast, flexible and easy-to-use framework to calculate the thermodynamics and elastic properties of crystalline solids. QUANTAS could be of use for researchers involved in various fields of solid-state chemistry, physics and mineralogy. Mineralogy, petrology and materials science are fundamental disciplines not only for the basic knowledge and classification of solid phases but also for their technological applications, which are becoming increasingly demanding and challenging. Characterization and design of materials are of utmost importance and usually need knowledge of the thermodynamics and mechanical stability of solids. Alongside well known experimental approaches, in recent years the advances in both quantum mechanical methods and computational power have placed theoretical investigations as a complementary useful and powerful tool in this kind of study. In order to aid both theoreticians and experimentalists, an open-source Python-based software, QUANTAS, has been developed. QUANTAS provides a fast, flexible, easy-to-use and extensible platform for calculating the thermodynamics and elastic behavior of crystalline solid phases, starting from both experimental and ab initio data.
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16
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Diamond and methane formation from the chemical decomposition of polyethylene at high pressures and temperatures. Sci Rep 2022; 12:631. [PMID: 35022446 PMCID: PMC8755720 DOI: 10.1038/s41598-021-04206-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Accepted: 12/07/2021] [Indexed: 11/08/2022] Open
Abstract
Polyethylene (C2H4)n was compressed to pressures between 10 and 30 GPa in a diamond anvil cell (DAC) and laser heated above 2500 K for approximately one second. This resulted in the chemical decomposition of the polymer into carbon and hydrocarbon reaction products. After quenching to ambient temperature, the decomposition products were measured in the DAC at pressures ranging from ambient to 29 GPa using a combination of x-ray diffraction (XRD) and small angle x-ray scattering (SAXS). XRD identified cubic diamond and methane as the predominant product species with their pressure-volume relationships exhibiting strong correlations to the diamond and methane equations of state. Length scales associated with the diamond products, obtained from SAXS measurements, indicate the formation of nanodiamonds with a radius of gyration between 12 and 35 nm consistent with 32-90 nm diameter spherical particles. These results are in good agreement with the predicted product composition under thermodynamic and chemical equilibrium.
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17
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Kong P, Minkov VS, Kuzovnikov MA, Drozdov AP, Besedin SP, Mozaffari S, Balicas L, Balakirev FF, Prakapenka VB, Chariton S, Knyazev DA, Greenberg E, Eremets MI. Superconductivity up to 243 K in the yttrium-hydrogen system under high pressure. Nat Commun 2021; 12:5075. [PMID: 34417471 PMCID: PMC8379216 DOI: 10.1038/s41467-021-25372-2] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 08/04/2021] [Indexed: 02/07/2023] Open
Abstract
The discovery of superconducting H3S with a critical temperature Tc∼200 K opened a door to room temperature superconductivity and stimulated further extensive studies of hydrogen-rich compounds stabilized by high pressure. Here, we report a comprehensive study of the yttrium-hydrogen system with the highest predicted Tcs among binary compounds and discuss the contradictions between different theoretical calculations and experimental data. We synthesized yttrium hydrides with the compositions of YH3, YH4, YH6 and YH9 in a diamond anvil cell and studied their crystal structures, electrical and magnetic transport properties, and isotopic effects. We found superconductivity in the Im-3m YH6 and P63/mmc YH9 phases with maximal Tcs of ∼220 K at 183 GPa and ∼243 K at 201 GPa, respectively. Fm-3m YH10 with the highest predicted Tc > 300 K was not observed in our experiments, and instead, YH9 was found to be the hydrogen-richest yttrium hydride in the studied pressure and temperature range up to record 410 GPa and 2250 K.
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Affiliation(s)
- Panpan Kong
- Max-Planck-Institut für Chemie, Mainz, Germany
| | | | - Mikhail A Kuzovnikov
- Institute of Solid State Physics Russian Academy of Sciences, Chernogolovka, Moscow District, Russia
| | | | | | - Shirin Mozaffari
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, USA
| | - Luis Balicas
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, USA
| | | | - Vitali B Prakapenka
- Center for Advanced Radiation Sources, University of Chicago, Chicago, IL, USA
| | - Stella Chariton
- Center for Advanced Radiation Sources, University of Chicago, Chicago, IL, USA
| | - Dmitry A Knyazev
- Max-Planck-Institut für Mikrostrukturphysik, Halle (Saale), Germany
| | - Eran Greenberg
- Center for Advanced Radiation Sources, University of Chicago, Chicago, IL, USA
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18
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Fedotenko T, Souza DS, Khandarkhaeva S, Dubrovinsky L, Dubrovinskaia N. Isothermal equation of state of crystalline and glassy materials from optical measurements in diamond anvil cells. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:063907. [PMID: 34243540 DOI: 10.1063/5.0050190] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 06/05/2021] [Indexed: 06/13/2023]
Abstract
Here, we present a method to study the equation of state of opaque amorphous and crystalline materials in diamond anvil cells. The approach is based on measurements of sample dimensions using high-resolution optical microscopy. Data on the volumetric strain as a function of pressure allow deriving the isothermal equation of state of the studied material. The analysis of optical images is fully automatized and allows measuring the sample dimensions with the precision of about 60 nm. The methodology was validated by studying isothermal compression of ω-Ti up to 30 GPa in a Ne pressure transmitting medium. Within the accuracy of the measurements, the bulk modulus of ω-Ti determined using optical microscopy was similar to that obtained from x-ray diffraction. For glassy carbon compressed to ∼30 GPa, the previously unknown bulk modulus was found to be equal to K0 = 28 (2) GPa [K' = 5.5(5)].
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Affiliation(s)
- T Fedotenko
- Material Physics and Technology at Extreme Conditions, Laboratory of Crystallography, University of Bayreuth, D-95440 Bayreuth, Germany
| | - D S Souza
- Bayerisches Geoinstitut Universität Bayreuth, D-95440 Bayreuth, Germany
| | - S Khandarkhaeva
- Material Physics and Technology at Extreme Conditions, Laboratory of Crystallography, University of Bayreuth, D-95440 Bayreuth, Germany
| | - L Dubrovinsky
- Bayerisches Geoinstitut Universität Bayreuth, D-95440 Bayreuth, Germany
| | - N Dubrovinskaia
- Material Physics and Technology at Extreme Conditions, Laboratory of Crystallography, University of Bayreuth, D-95440 Bayreuth, Germany
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19
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Reffas M, Fatmi M, Cherrad D, Haddadi K, Medkour Y, Saoudi A, Roumili A, Louail L. Theoretical Study of Structural, Electronic, Optical, and Elastic Properties of KLiX (X: S, Se, and Te) under Hydrostatic Pressure: A Pseudo Potential Plane Wave (PP-PW) Contribution. CRYSTALLOGR REP+ 2021. [DOI: 10.1134/s1063774521030202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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20
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MacLeod SG, Errandonea D, Cox GA, Cynn H, Daisenberger D, Finnegan SE, McMahon MI, Munro KA, Popescu C, Storm CV. The phase diagram of Ti-6Al-4V at high-pressures and high-temperatures. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:154001. [PMID: 33498030 DOI: 10.1088/1361-648x/abdffa] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 01/26/2021] [Indexed: 06/12/2023]
Abstract
We report results from a series of diamond-anvil-cell synchrotron x-ray diffraction and large-volume-press experiments, and calculations, to investigate the phase diagram of commercial polycrystalline high-strength Ti-6Al-4V alloy in pressure-temperature space. Up to ∼30 GPa and 886 K, Ti-6Al-4V is found to be stable in the hexagonal-close-packed, orαphase. The effect of temperature on the volume expansion and compressibility ofα-Ti-6Al-4V is modest. The martensiticα→ω(hexagonal) transition occurs at ∼30 GPa, with both phases coexisting until at ∼38-40 GPa the transition to theωphase is completed. Between 300 K and 844 K theα→ωtransition appears to be independent of temperature.ω-Ti-6Al-4V is stable to ∼91 GPa and 844 K, the highest combined pressure and temperature reached in these experiments. Pressure-volume-temperature equations-of-state for theαandωphases of Ti-6Al-4V are generated and found to be similar to pure Ti. A pronounced hysteresis is observed in theω-Ti-6Al-4V on decompression, with the hexagonal structure reverting back to theαphase at pressures below ∼9 GPa at room temperature, and at a higher pressure at elevated temperatures. Based on our data, we estimate the Ti-6Al-4Vα-β-ωtriple point to occur at ∼900 K and 30 GPa, in good agreement with our calculations.
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Affiliation(s)
- S G MacLeod
- AWE, Aldermaston, Reading, RG7 4PR, United Kingdom
- SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Peter Guthrie Tait Road, Edinburgh, EH9 3FD, United Kingdom
| | - D Errandonea
- Departmento de Física Aplicada-ICMUV, Universidad de Valencia, MALTA Consolider Team, Edificio de Investigación, C/Dr. Moliner 50, 46100 Burjassot, Valencia, Spain
| | - G A Cox
- AWE, Aldermaston, Reading, RG7 4PR, United Kingdom
| | - H Cynn
- Lawrence Livermore National Laboratory, Livermore, California 94550, United States of America
| | - D Daisenberger
- Diamond Light Source Ltd., Harwell Science & Innovation Campus, Didcot, Oxfordshire, OX11 0DE, United Kingdom
| | - S E Finnegan
- SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Peter Guthrie Tait Road, Edinburgh, EH9 3FD, United Kingdom
| | - M I McMahon
- SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Peter Guthrie Tait Road, Edinburgh, EH9 3FD, United Kingdom
| | - K A Munro
- SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Peter Guthrie Tait Road, Edinburgh, EH9 3FD, United Kingdom
| | - C Popescu
- CELLS-ALBA Synchrotron Light Facility, Cerdanyola del Vallès 08290, Barcelona, Spain
| | - C V Storm
- SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Peter Guthrie Tait Road, Edinburgh, EH9 3FD, United Kingdom
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21
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Guńka PA, Olejniczak A, Fanetti S, Bini R, Collings IE, Svitlyk V, Dziubek KF. Crystal Structure and Non-Hydrostatic Stress-Induced Phase Transition of Urotropine Under High Pressure. Chemistry 2021; 27:1094-1102. [PMID: 33095457 DOI: 10.1002/chem.202003928] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Indexed: 11/07/2022]
Abstract
High-pressure behavior of hexamethylenetetramine (urotropine) was studied in situ using angle-dispersive single-crystal synchrotron X-ray diffraction (XRD) and Fourier-transform infrared absorption (FTIR) spectroscopy. Experiments were conducted in various pressure-transmitting media to study the effect of deviatoric stress on phase transformations. Up to 4 GPa significant damping of molecular librations and atomic thermal motion was observed. A first-order phase transition to a tetragonal structure was observed with an onset at approximately 12.5 GPa and characterized by sluggish kinetics and considerable hysteresis upon decompression. However, it occurs only in non-hydrostatic conditions, induced by deviatoric or uniaxial stress in the sample. This behavior finds analogies in similar cubic crystals built of highly symmetric cage-like molecules and may be considered a common feature of such systems. DFT computations were performed to model urotropine equation of state and pressure dependence of vibrational modes. The first successful Hirshfeld atom refinements carried out for high-pressure diffraction data are reported. The refinements yielded more realistic C-H bond lengths than the independent atom model even though the high-pressure diffraction data are incomplete.
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Affiliation(s)
- Piotr A Guńka
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00664, Warszawa, Poland
| | - Anna Olejniczak
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61614, Poznań, Poland
| | - Samuele Fanetti
- Instituto di Chimica dei Composti Organo-Metallici, CNR-ICCOM, Via Madonna del Piano 10, 50019, Sesto Fiorentino, Italy.,LENS, European Laboratory for Nonlinear Spectroscopy, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy
| | - Roberto Bini
- Instituto di Chimica dei Composti Organo-Metallici, CNR-ICCOM, Via Madonna del Piano 10, 50019, Sesto Fiorentino, Italy.,LENS, European Laboratory for Nonlinear Spectroscopy, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy.,Dipartimento di Chimica, Università degli Studi di Firenze, Via della Lastruccia 13, 50019, Sesto Fiorentino, Italy
| | - Ines E Collings
- European Synchrotron Radiation Facility 71, avenue des Martyrs, CS 40220, 38043, Grenoble, France.,current address: Center for X-ray Analytics, Empa-Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600, Dübendorf, Switzerland
| | - Volodymyr Svitlyk
- European Synchrotron Radiation Facility 71, avenue des Martyrs, CS 40220, 38043, Grenoble, France
| | - Kamil F Dziubek
- LENS, European Laboratory for Nonlinear Spectroscopy, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy
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22
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Luo D, Qiao X, Dronskowski R. Predicting Nitrogen-Based Families of Compounds: Transition-Metal Guanidinates TCN 3 (T=V, Nb, Ta) and Ortho-Nitrido Carbonates T' 2 CN 4 (T'=Ti, Zr, Hf). Angew Chem Int Ed Engl 2021; 60:486-492. [PMID: 33001558 PMCID: PMC7821139 DOI: 10.1002/anie.202011196] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 09/28/2020] [Indexed: 11/17/2022]
Abstract
Due to its unsurpassed capability to engage in various sp hybridizations or orbital mixings, carbon may contribute in expanding solid-state nitrogen chemistry by allowing for different complex anions, such as the known NCN2- carbodiimide unit, the so far unknown CN3 5- guanidinate anion, and the likewise unknown CN4 8- ortho-nitrido carbonate (onc) entity. Because the latter two complex anions have never been observed before, we have chemically designed them using first-principles structural searches, and we here predict the first hydrogen-free guanidinates TCN3 (T=V, Nb, Ta) and ortho-nitrido carbonates T'2 CN4 (T'=Ti, Zr, Hf) being mechanically stable at normal pressure; the latter should coexist as solid solutions with the stoichiometrically identical nitride carbodiimides and nitride guanidinates. We also suggest favorable exothermic reactions as useful signposts for eventual synthesis, and we trust that the decay of the novel compounds is unlikely due to presumably large kinetic activation barriers (C-N bond breaking) and quite substantial Madelung energies stabilizing the highly charged complex anions. While chemical-bonding analysis reveals the novel CN4 8- to be more covalent compared to NCN2- and CN3 5- within related compounds, further electronic-structure data of onc phases hint at their physicochemical potential in terms of photoelectrochemical water splitting and nonlinear optics.
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Affiliation(s)
- Dongbao Luo
- Hoffmann Institute of Advanced MaterialsShenzhen Polytechnic7098 Liuxian Blvd, Nanshan DistrictShenzhenChina
- Chair of Solid-State and Quantum ChemistryInstitute of Inorganic ChemistryRWTH Aachen University52056AachenGermany
| | - Xianji Qiao
- Chair of Solid-State and Quantum ChemistryInstitute of Inorganic ChemistryRWTH Aachen University52056AachenGermany
| | - Richard Dronskowski
- Hoffmann Institute of Advanced MaterialsShenzhen Polytechnic7098 Liuxian Blvd, Nanshan DistrictShenzhenChina
- Chair of Solid-State and Quantum ChemistryInstitute of Inorganic ChemistryRWTH Aachen University52056AachenGermany
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23
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Luo D, Qiao X, Dronskowski R. Vorhersage stickstoffbasierter Verbindungsklassen: Guanidinate
T
CN
3
(
T
=V, Nb, Ta) und Orthonitridocarbonate
T′
2
CN
4
(
T′
=Ti, Zr, Hf) von Übergangsmetallen. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202011196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dongbao Luo
- Hoffmann Institute of Advanced Materials Shenzhen Polytechnic 7098 Liuxian Blvd, Bezirk Nanshan Shenzhen China
- Lehrstuhl für Festkörper- und Quantenchemie Institut für Anorganische Chemie RWTH Aachen University 52056 Aachen Deutschland
| | - Xianji Qiao
- Lehrstuhl für Festkörper- und Quantenchemie Institut für Anorganische Chemie RWTH Aachen University 52056 Aachen Deutschland
| | - Richard Dronskowski
- Hoffmann Institute of Advanced Materials Shenzhen Polytechnic 7098 Liuxian Blvd, Bezirk Nanshan Shenzhen China
- Lehrstuhl für Festkörper- und Quantenchemie Institut für Anorganische Chemie RWTH Aachen University 52056 Aachen Deutschland
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24
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Guńka PA, Hanfland M, Chen YS, Zachara J. High-pressure and low-temperature structural study of claudetite I, a monoclinic layered As 2O 3 polymorph. CrystEngComm 2021. [DOI: 10.1039/d0ce01401j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
High-pressure structural studies of claudetite I reveal that it exhibits the lowest As coordination numbers despite being the densest As2O3 polymorph.
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Affiliation(s)
- Piotr A. Guńka
- Faculty of Chemistry
- Warsaw University of Technology
- 00-664 Warszawa
- Poland
| | | | - Yu-Sheng Chen
- NSF's ChemMatCARS
- Center for Advanced Radiation Source
- The University of Chicago
- Lemont
- USA
| | - Janusz Zachara
- Faculty of Chemistry
- Warsaw University of Technology
- 00-664 Warszawa
- Poland
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25
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Nghia NV, Hieu HK, Duc NB, Hiep TP. Investigation of pressure effects on melting temperature and shear modulus of B1-LiF. Chem Phys 2020. [DOI: 10.1016/j.chemphys.2020.110862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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26
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Wharmby MT, Niekiel F, Benecke J, Waitschat S, Reinsch H, Daisenberger D, Stock N, Yot PG. Influence of Thermal and Mechanical Stimuli on the Behavior of Al-CAU-13 Metal-Organic Framework. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E1698. [PMID: 32872371 PMCID: PMC7557782 DOI: 10.3390/nano10091698] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 08/24/2020] [Accepted: 08/25/2020] [Indexed: 11/17/2022]
Abstract
The response of the metal-organic framework aluminum-1,4-cyclohexanedicarboxylate or Al-CAU-13 (CAU: Christian Albrecht University) to the application of thermal and mechanical stimuli was investigated using synchrotron powder X-ray diffraction (SPXRD). Variable temperature in situ SPXRD data, over the range 80-500 K, revealed a complex evolution of the structure of the water guest containing Al-CAU-13H2O, the dehydration process from ca. 310 to 370 K, and also the evolution of the guest free Al-CAU-13 structure between ca. 370 and 500 K. Rietveld refinement allowed this complexity to be rationalized in the different regions of heating. The Berman thermal Equation of State was determined for the two structures (Al-CAU-13H2O and Al-CAU-13). Diamond anvil cell studies at elevated pressure (from ambient to up to ca. 11 GPa) revealed similarities in the structural responses on application of pressure and temperature. The ability of the pressure medium to penetrate the framework was also found to be important: non-penetrating silicone oil caused pressure induced amorphization, whereas penetrating helium showed no plastic deformation of the structure. Third-order Vinet equations of state were calculated and show Al-CAU-13H2O is a hard compound for a metal-organic framework material. The mechanical response of Al-CAU-13, with tetramethylpyrazine guests replacing water, was also investigated. Although the connectivity of the structure is the same, all the linkers have a linear e,e-conformation and the structure adopts a more open, wine-rack-like arrangement, which demonstrates negative linear compressibility (NLC) similar to Al-MIL-53 and a significantly softer mechanical response. The origin of this variation in behavior is attributed to the different linker conformation, demonstrating the influence of the S-shaped a,a-conformation on the response of the framework to external stimuli.
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Affiliation(s)
- Michael T. Wharmby
- Deutsches Elektronen-Synchrotron (DESY), Notkestr. 85, D-22607 Hamburg, Germany
| | - Felicitas Niekiel
- Institut für Anorganische Chemie, Christian Albrechts Universität zu Kiel, Max-Eyth-Straße 2, D-24118 Kiel, Germany; (F.N.); (J.B.); (S.W.); (H.R.); (N.S.)
| | - Jannik Benecke
- Institut für Anorganische Chemie, Christian Albrechts Universität zu Kiel, Max-Eyth-Straße 2, D-24118 Kiel, Germany; (F.N.); (J.B.); (S.W.); (H.R.); (N.S.)
| | - Steve Waitschat
- Institut für Anorganische Chemie, Christian Albrechts Universität zu Kiel, Max-Eyth-Straße 2, D-24118 Kiel, Germany; (F.N.); (J.B.); (S.W.); (H.R.); (N.S.)
| | - Helge Reinsch
- Institut für Anorganische Chemie, Christian Albrechts Universität zu Kiel, Max-Eyth-Straße 2, D-24118 Kiel, Germany; (F.N.); (J.B.); (S.W.); (H.R.); (N.S.)
| | - Dominik Daisenberger
- Diamond Light Source Ltd., Diamond House, Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK;
| | - Norbert Stock
- Institut für Anorganische Chemie, Christian Albrechts Universität zu Kiel, Max-Eyth-Straße 2, D-24118 Kiel, Germany; (F.N.); (J.B.); (S.W.); (H.R.); (N.S.)
| | - Pascal G. Yot
- ICGM, University Montpellier, CNRS, ENSCM, F-34095 Montpellier, France
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27
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Eidelstein E, Barzilai S, Curtarolo S, Levy O. First Principles Investigation of Cold Curves of Metals. Isr J Chem 2020. [DOI: 10.1002/ijch.201900096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Eitan Eidelstein
- Department of Physics NRCN P.O. Box 9001 Beer-Sheva 84190 Israel
- Department of Chemistry Tel-Aviv University Tel Aviv 69978 Israel
| | - Shmuel Barzilai
- Department of Chemistry NRCN P.O. Box 9001 Beer-Sheva 84190 Israel
| | - Stefano Curtarolo
- Department of Mechanical Engineering and Materials Science Duke University Durham, NC 27708 USA
| | - Ohad Levy
- Department of Physics NRCN P.O. Box 9001 Beer-Sheva 84190 Israel
- Department of Mechanical Engineering and Materials Science Duke University Durham, NC 27708 USA
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28
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Abstract
The physical properties of argon (Ar) are investigated to 382 GPa and 3000 K using diamond anvil cell experiments and first-principles molecular dynamics. The estimated density of Ar is smaller that of the Preliminary reference Earth model (PREM) mantle, which indicates that the density crossover does not occur at the bottom of the lower mantle. A large volume dependence of the thermal pressure of Ar is revealed at pressures higher than 200 GPa, and a significant temperature dependence of the calculated effective Grüneisen parameters is confirmed at high pressures. A melting temperature of Ar is estimated from the calculation data and a significant pressure dependence is confirmed. If the pressure-temperature path of the subducted slab is lower than the critical condition, ~750 K and ~7.5 GPa, solid Ar can be carried down into the deep mantle. Melting of solid Ar in the upwelling mantle plume occurs at the bottom of the transition zone. Thus, solid Ar plays an important role in Ar recycling in the Earth’s interior.
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Affiliation(s)
- Shigeaki Ono
- Volcanoes and Earth's Interior Research Center, Research Institute for Marine Geodynamics, Japan Agency for Marine-Earth Science and Technology, 2-15 Natsushima-cho, Yokosuka, Kanagawa, 237-0061, Japan.
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29
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Synchrotron infrared spectroscopic evidence of the probable transition to metal hydrogen. Nature 2020; 577:631-635. [DOI: 10.1038/s41586-019-1927-3] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 11/26/2019] [Indexed: 11/08/2022]
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30
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Owens-Baird B, Wang J, Wang SG, Chen YS, Lee S, Donadio D, Kovnir K. III-V Clathrate Semiconductors with Outstanding Hole Mobility: Cs 8In 27Sb 19 and A8Ga 27Sb 19 ( A = Cs, Rb). J Am Chem Soc 2020; 142:2031-2041. [PMID: 31894979 DOI: 10.1021/jacs.9b12351] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Three novel unconventional clathrates with unprecedented III-V semiconducting frameworks have been synthesized: Cs8In27Sb19, Cs8Ga27Sb19, and Rb8Ga27Sb19. These clathrates represent the first examples of tetrel-free clathrates that are completely composed of main group elements. All title compounds crystallize in an ordered superstructure of clathrate-I in the Ia3̅ space group (No. 206; Z = 8). In the clathrate framework, a full ordering of {Ga or In} and Sb is observed by a combination of high-resolution synchrotron single-crystal and powder X-ray diffraction techniques. Density functional theory (DFT) calculations show that all three clathrates are energetically stable with relaxed lattice constants matching the experimental data. Due to the complexity of the crystal structure composed of heavy elements, the reported clathrates exhibit ultralow thermal conductivities of less than 1 W·m-1·K-1 at room temperature. All compounds are predicted and experimentally confirmed to be narrow-bandgap p-type semiconductors with high Seebeck thermopower values, up to 250 μV·K-1 at 300 K for Cs8In27Sb19. The latter compound shows carrier concentrations and mobilities, 1.42 × 1015 cm-3 and 880 cm2 ·V-1·s-1, which are on par with the values for parent binary InSb, one of the best electronic semiconductors. The high hole carrier mobility is uncommon for complex bulk materials and a highly desirable trait, opening ways to design semiconducting materials based on tunable III-V clathrates.
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Affiliation(s)
- Bryan Owens-Baird
- Department of Chemistry , Iowa State University , Ames , Iowa 50011 , United States.,Ames Laboratory , U.S. Department of Energy , Ames , Iowa 50011 , United States
| | - Jian Wang
- Department of Chemistry , Iowa State University , Ames , Iowa 50011 , United States.,Ames Laboratory , U.S. Department of Energy , Ames , Iowa 50011 , United States.,Department of Chemistry , Wichita State University , Wichita , Kansas 67260 , United States
| | - Suyin Grass Wang
- NSF's ChemMatCARS, Center for Advanced Radiation Sources, Argonne National Laboratory , The University of Chicago , Lemont , Illinois 60439 , United States
| | - Yu-Sheng Chen
- NSF's ChemMatCARS, Center for Advanced Radiation Sources, Argonne National Laboratory , The University of Chicago , Lemont , Illinois 60439 , United States
| | - Shannon Lee
- Department of Chemistry , Iowa State University , Ames , Iowa 50011 , United States.,Ames Laboratory , U.S. Department of Energy , Ames , Iowa 50011 , United States
| | - Davide Donadio
- Department of Chemistry , University of California, Davis , Davis , California 95616 , United States
| | - Kirill Kovnir
- Department of Chemistry , Iowa State University , Ames , Iowa 50011 , United States.,Ames Laboratory , U.S. Department of Energy , Ames , Iowa 50011 , United States
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31
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Quasi-hydrostatic equation of state of silicon up to 1 megabar at ambient temperature. Sci Rep 2019; 9:15537. [PMID: 31664104 PMCID: PMC6820762 DOI: 10.1038/s41598-019-51931-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 10/08/2019] [Indexed: 11/25/2022] Open
Abstract
The isothermal equation of state of silicon has been determined by synchrotron x-ray diffraction experiments up to 105.2 GPa at room temperature using diamond anvil cells. A He-pressure medium was used to minimize the effect of uniaxial stress on the sample volume and ruby, gold and tungsten pressure gauges were used. Seven different phases of silicon have been observed along the experimental conditions covered in the present study.
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32
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Anzellini S, Errandonea D, Cazorla C, MacLeod S, Monteseguro V, Boccato S, Bandiello E, Anichtchenko DD, Popescu C, Beavers CM. Thermal equation of state of ruthenium characterized by resistively heated diamond anvil cell. Sci Rep 2019; 9:14459. [PMID: 31595017 PMCID: PMC6783540 DOI: 10.1038/s41598-019-51037-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 09/24/2019] [Indexed: 11/09/2022] Open
Abstract
The high-pressure and high-temperature structural and chemical stability of ruthenium has been investigated via synchrotron X-ray diffraction using a resistively heated diamond anvil cell. In the present experiment, ruthenium remains stable in the hcp phase up to 150 GPa and 960 K. The thermal equation of state has been determined based upon the data collected following four different isotherms. A quasi-hydrostatic equation of state at ambient temperature has also been characterized up to 150 GPa. The measured equation of state and structural parameters have been compared to the results of ab initio simulations performed with several exchange-correlation functionals. The agreement between theory and experiments is generally quite good. Phonon calculations were also carried out to show that hcp ruthenium is not only structurally but also dynamically stable up to extreme pressures. These calculations also allow the pressure dependence of the Raman-active E2g mode and the silent B1g mode of Ru to be determined.
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Affiliation(s)
- Simone Anzellini
- Diamond Light Source Ltd., Harwell Science & Innovation Campus, Diamond House, Didcot, OX11 0DE, UK.
| | - Daniel Errandonea
- Departamento de Física Aplicada - Instituto de Ciencia de Materiales, Matter at High Pressure (MALTA) Consolider Team, Universidad de Valencia, Edificio de Investigación, C/Dr. Moliner 50, Burjassot, 46100, Valencia, Spain
| | - Claudio Cazorla
- School of Materials Science and Engineering, University of New South Wales Sydney, Sydney, New South Wales, 2052, Australia
| | - Simon MacLeod
- AWE, Aldermaston, Reading, RG7 4PR, United Kingdom.,SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
| | - Virginia Monteseguro
- Departamento de Física Aplicada - Instituto de Ciencia de Materiales, Matter at High Pressure (MALTA) Consolider Team, Universidad de Valencia, Edificio de Investigación, C/Dr. Moliner 50, Burjassot, 46100, Valencia, Spain
| | - Silvia Boccato
- Institut de Minéralogie, de Physique des Matériaux, et de Cosmochimie (IMPMC), Sorbonne Université - UPMC, UMR CNRS 7590, Muséum National d'Histoire Naturelle, IRD UMR 206, F-75005, Paris, France
| | - Enrico Bandiello
- Departamento de Física Aplicada - Instituto de Ciencia de Materiales, Matter at High Pressure (MALTA) Consolider Team, Universidad de Valencia, Edificio de Investigación, C/Dr. Moliner 50, Burjassot, 46100, Valencia, Spain
| | - Daniel Diaz Anichtchenko
- Departamento de Física Aplicada - Instituto de Ciencia de Materiales, Matter at High Pressure (MALTA) Consolider Team, Universidad de Valencia, Edificio de Investigación, C/Dr. Moliner 50, Burjassot, 46100, Valencia, Spain
| | - Catalin Popescu
- CELLS-ALBA Synchrotron Light Facility, 08290 Cerdanyola, Barcelona, Spain
| | - Christine M Beavers
- Diamond Light Source Ltd., Harwell Science & Innovation Campus, Diamond House, Didcot, OX11 0DE, UK
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Abstract
Using X-ray emission spectroscopy, we find appreciable local magnetic moments until 30 GPa to 40 GPa in the high-pressure phase of iron; however, no magnetic order is detected with neutron powder diffraction down to 1.8 K, contrary to previous predictions. Our first-principles calculations reveal a "spin-smectic" state lower in energy than previous results. This state forms antiferromagnetic bilayers separated by null spin bilayers, which allows a complete relaxation of the inherent frustration of antiferromagnetism on a hexagonal close-packed lattice. The magnetic bilayers are likely orientationally disordered, owing to the soft interlayer excitations and the near-degeneracy with other smectic phases. This possible lack of long-range correlation agrees with the null results from neutron powder diffraction. An orientationally disordered, spin-smectic state resolves previously perceived contradictions in high-pressure iron and could be integral to explaining its puzzling superconductivity.
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34
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Dewaele A, Rosa AD, Guignot N. Argon-neon binary diagram and ArNe 2 Laves phase. J Chem Phys 2019; 151:124708. [PMID: 31575214 DOI: 10.1063/1.5119419] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Mixtures of argon and neon have been experimentally studied under high pressure. One stoichiometric compound, with ArNe2 composition, is observed in this system. It is a Laves phase with a hexagonal MgZn2 structure, stable up to at least 65 GPa, the highest pressure reached in the experiments. Its equation of state follows closely the one of an ideal Ar+2Ne mixture. The binary phase diagram of the Ar-Ne system resembles the diagram predicted for hard sphere mixtures with a similar atomic radius ratio, suggesting that no electronic interactions appear in this system in this pressure range. ArNe2 can be a convenient quasihydrostatic pressure transmitting medium under moderate pressure.
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35
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Daghash SM, Servio P, Rey AD. Structural properties of sH hydrate: a DFT study of anisotropy and equation of state. MOLECULAR SIMULATION 2019. [DOI: 10.1080/08927022.2019.1660326] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Shaden M. Daghash
- Department of Chemical Engineering, McGill University, Montréal, Canada
| | - Phillip Servio
- Department of Chemical Engineering, McGill University, Montréal, Canada
| | - Alejandro D. Rey
- Department of Chemical Engineering, McGill University, Montréal, Canada
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36
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Fischer M, Kim WJ, Badawi M, Lebègue S. Benchmarking the performance of approximate van der Waals methods for the structural and energetic properties of SiO 2 and AlPO 4 frameworks. J Chem Phys 2019; 150:094102. [PMID: 30849891 DOI: 10.1063/1.5085394] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Density functional theory (DFT) calculations using sixteen different approaches, fourteen of which were designed to include dispersion interactions [DFT + D and van der Waals (vdW)-DF methods], were performed for a set of sixteen framework compounds with either SiO2 or AlPO4 composition. The compounds include four dense structures (α-quartz, α-cristobalite, and their AlPO4 analogues), eight all-silica zeolites, and four aluminophosphate zeotypes (AlPOs). We analyzed the performance in reproducing the equilibrium structure for all systems, and computed bulk moduli and relative stabilities were compared to experiments for those compounds where experimental data are available. We found that the results obtained with functionals that take into account dispersive interactions are closer to experiments than those obtained with a bare generalized gradient functional. However, the variation among individual methods is considerable, and functionals that perform well for one quantity may give rather large deviations for another. Taking together the whole body of results, it appears that the Perdew-Burke-Ernzerhof functional including a many-body dispersion correction and the rev-vdW-DF2 methods present the best performance for the description of SiO2 and AlPO4 materials.
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Affiliation(s)
- Michael Fischer
- Crystallography Group, Department of Geosciences, University of Bremen, Klagenfurter Straße 2-4, D-28359 Bremen, Germany
| | - Won June Kim
- Université de Lorraine and CNRS, LPCT, UMR 7019, 54506 Vandœuvre-lès-Nancy, France
| | - Michael Badawi
- Université de Lorraine and CNRS, LPCT, UMR 7019, 54506 Vandœuvre-lès-Nancy, France
| | - Sébastien Lebègue
- Université de Lorraine and CNRS, LPCT, UMR 7019, 54506 Vandœuvre-lès-Nancy, France
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37
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Hoffman AE, Wieme J, Rogge SM, Vanduyfhuys L, Van Speybroeck V. The impact of lattice vibrations on the macroscopic breathing behavior of MIL-53(Al). ACTA ACUST UNITED AC 2019. [DOI: 10.1515/zkri-2018-2154] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Abstract
The mechanism inducing the breathing in flexible metal-organic frameworks, such as MIL-53(Al), is still not fully understood. Herein, the influence of lattice vibrations on the breathing transition in MIL-53(Al) is investigated to gain insight in this phenomenon. Through solid-state density-functional theory calculations, the volume-dependent IR spectrum is computed together with the volume-frequency relations of all vibrational modes. Furthermore, important thermodynamic properties such as the Helmholtz free energy, the specific heat capacity, the bulk modulus, and the volumetric thermal expansion coefficient are derived via these volume-frequency relations using the quasi-harmonic approximation. The simulations expose a general volume-dependency of the vibrations with wavenumbers above 300 cm−1 due to their localized nature. In contrast, a diverse set of volume-frequency relations are observed for vibrations in the terahertz region (<300 cm−1) containing the vibrations exhibiting collective behavior. Some terahertz vibrations display large frequency differences over the computed volume range, induced by either repulsion or strain effects, potentially triggering the phase transformation. Finally, the impact of the lattice vibrations on the thermodynamic properties is investigated. This reveals that the closed pore to large pore phase transformation in MIL-53(Al) is mainly facilitated by terahertz vibrations inducing rotations of the organic linker, while the large pore to closed pore phase transformation relies on two framework-specific soft modes.
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Affiliation(s)
- Alexander E.J. Hoffman
- Center for Molecular Modeling, Ghent University , Technologiepark 46 , 9052 Zwijnaarde , Belgium
| | - Jelle Wieme
- Center for Molecular Modeling, Ghent University , Technologiepark 46 , 9052 Zwijnaarde , Belgium
| | - Sven M.J. Rogge
- Center for Molecular Modeling, Ghent University , Technologiepark 46 , 9052 Zwijnaarde , Belgium
| | - Louis Vanduyfhuys
- Center for Molecular Modeling, Ghent University , Technologiepark 46 , 9052 Zwijnaarde , Belgium
| | - Veronique Van Speybroeck
- Center for Molecular Modeling, Ghent University , Technologiepark 46 , 9052 Zwijnaarde , Belgium
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38
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Bull CL, Funnell NP, Ridley CJ, Pulham CR, Coster PL, Tellam JP, Marshall WG. Pressure-induced isosymmetric phase transition in biurea. CrystEngComm 2019. [DOI: 10.1039/c9ce01028a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An isosymmetric phase transition of biurea has been found in which the molecules appear to “snap” from one conformer to another upon compression.
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Affiliation(s)
- Craig L. Bull
- ISIS Neutron and Muon Facility
- Rutherford Appleton Laboratory
- Chilton
- U. K
| | | | | | - Colin R. Pulham
- EastCHEM School of Chemistry
- Joseph Black Building
- Edinburgh
- UK
| | - Paul L. Coster
- EastCHEM School of Chemistry
- Joseph Black Building
- Edinburgh
- UK
| | - James P. Tellam
- ISIS Neutron and Muon Facility
- Rutherford Appleton Laboratory
- Chilton
- U. K
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39
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Giordano N, Beavers CM, Kamenev KV, Marshall WG, Moggach SA, Patterson SD, Teat SJ, Warren JE, Wood PA, Parsons S. High-pressure polymorphism in l-threonine between ambient pressure and 22 GPa. CrystEngComm 2019. [DOI: 10.1039/c9ce00388f] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The amino acid l-threonine undergoes three phase transitions between ambient pressure and 22.3 GPa which modify both hydrogen bonding and the molecular conformation.
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Affiliation(s)
- Nico Giordano
- Centre for Science at Extreme Conditions and EaStCHEM School of Chemistry
- The University of Edinburgh
- Edinburgh
- UK
- Advanced Light Source
| | - Christine M. Beavers
- Advanced Light Source
- Berkeley
- USA
- Department of Earth & Planetary Sciences
- University of California
| | - Konstantin V. Kamenev
- Centre for Science at Extreme Conditions and School of Engineering
- The University of Edinburgh
- Edinburgh
- UK
| | - William G. Marshall
- ISIS Pulsed Neutron and Muon Facility
- STFC Rutherford Appleton Laboratory
- Harwell Science and Innovation Campus
- Harwell Oxford
- UK
| | - Stephen A. Moggach
- Centre for Science at Extreme Conditions and EaStCHEM School of Chemistry
- The University of Edinburgh
- Edinburgh
- UK
| | - Simon D. Patterson
- Centre for Science at Extreme Conditions and EaStCHEM School of Chemistry
- The University of Edinburgh
- Edinburgh
- UK
| | | | - John E. Warren
- Synchrotron Radiation Source
- CCLRC Daresbury Laboratory
- Warrington
- UK
| | | | - Simon Parsons
- Centre for Science at Extreme Conditions and EaStCHEM School of Chemistry
- The University of Edinburgh
- Edinburgh
- UK
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40
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Tuning the balance between dispersion and entropy to design temperature-responsive flexible metal-organic frameworks. Nat Commun 2018; 9:4899. [PMID: 30464249 PMCID: PMC6249296 DOI: 10.1038/s41467-018-07298-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 10/25/2018] [Indexed: 11/09/2022] Open
Abstract
Temperature-responsive flexibility in metal-organic frameworks (MOFs) appeals to the imagination. The ability to transform upon thermal stimuli while retaining a given crystalline topology is desired for specialized sensors and actuators. However, rational design of such shape-memory nanopores is hampered by a lack of knowledge on the nanoscopic interactions governing the observed behavior. Using the prototypical MIL-53(Al) as a starting point, we show that the phase transformation between a narrow-pore and large-pore phase is determined by a delicate balance between dispersion stabilization at low temperatures and entropic effects at higher ones. We present an accurate theoretical framework that allows designing breathing thermo-responsive MOFs, based on many-electron data for the dispersion interactions and density-functional theory entropy contributions. Within an isoreticular series of materials, MIL-53(Al), MIL-53(Al)-FA, DUT-4, DUT-5 and MIL-53(Ga), only MIL-53(Al) and MIL-53(Ga) are proven to switch phases within a realistic temperature range. Rational design of metal organic frameworks (MOFs) with shape-memory nanopores is a formidable challenge. Here the authors use an accurate theoretical approach to design thermo-responsive MOFs based on a balance of van der Waals and entropy contributions.
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41
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Duc NB, Tho VQ, Tien TS, Khoa DQ, Hieu HK. Pressure and temperature dependence of EXAFS Debye-Waller factor of platinum. Radiat Phys Chem Oxf Engl 1993 2018. [DOI: 10.1016/j.radphyschem.2018.03.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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42
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Irving JCE, Cottaar S, Lekić V. Seismically determined elastic parameters for Earth's outer core. SCIENCE ADVANCES 2018; 4:eaar2538. [PMID: 29963624 PMCID: PMC6021139 DOI: 10.1126/sciadv.aar2538] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 05/18/2018] [Indexed: 06/08/2023]
Abstract
Turbulent convection of the liquid iron alloy outer core generates Earth's magnetic field and supplies heat to the mantle. The exact composition of the iron alloy is fundamentally linked to the processes powering the convection and can be constrained by its seismic properties. Discrepancies between seismic models determined using body waves and normal modes show that these properties are not yet fully agreed upon. In addition, technical challenges in experimentally measuring the equation-of-state (EoS) parameters of liquid iron alloys at high pressures and temperatures further complicate compositional inferences. We directly infer EoS parameters describing Earth's outer core from normal mode center frequency observations and present the resulting Elastic Parameters of the Outer Core (EPOC) seismic model. Unlike alternative seismic models, ours requires only three parameters and guarantees physically realistic behavior with increasing pressure for a well-mixed homogeneous material along an isentrope, consistent with the outer core's condition. We show that EPOC predicts available normal mode frequencies better than the Preliminary Reference Earth Model (PREM) while also being more consistent with body wave-derived models, eliminating a long-standing discrepancy. The velocity at the top of the outer core is lower, and increases with depth more steeply, in EPOC than in PREM, while the density in EPOC is higher than that in PREM across the outer core. The steeper profiles and higher density imply that the outer core comprises a lighter but more compressible alloy than that inferred for PREM. Furthermore, EPOC's steeper velocity gradient explains differential SmKS body wave travel times better than previous one-dimensional global models, without requiring an anomalously slow ~90- to 450-km-thick layer at the top of the outer core.
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Affiliation(s)
| | - Sanne Cottaar
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
| | - Vedran Lekić
- Department of Geology, University of Maryland, College Park, MD 20742, USA
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43
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Hendrickx K, Joos JJ, De Vos A, Poelman D, Smet PF, Van Speybroeck V, Van Der Voort P, Lejaeghere K. Exploring Lanthanide Doping in UiO-66: A Combined Experimental and Computational Study of the Electronic Structure. Inorg Chem 2018; 57:5463-5474. [DOI: 10.1021/acs.inorgchem.8b00425] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kevin Hendrickx
- Center for Ordered Materials, Organometallics and Catalysis (COMOC), Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3), 9000 Gent, Belgium
- Center for Molecular Modeling (CMM), Ghent University, Technologiepark 903, 9052 Zwijnaarde, Belgium
| | - Jonas J. Joos
- LumiLab, Department of Solid State Sciences, Ghent University, Krijgslaan 281 (S1), 9000 Gent, Belgium
- Center for Nano- and Biophotonics (NB Photonics), Ghent University, 9000 Gent, Belgium
| | - Arthur De Vos
- Center for Molecular Modeling (CMM), Ghent University, Technologiepark 903, 9052 Zwijnaarde, Belgium
| | - Dirk Poelman
- LumiLab, Department of Solid State Sciences, Ghent University, Krijgslaan 281 (S1), 9000 Gent, Belgium
- Center for Nano- and Biophotonics (NB Photonics), Ghent University, 9000 Gent, Belgium
| | - Philippe F. Smet
- LumiLab, Department of Solid State Sciences, Ghent University, Krijgslaan 281 (S1), 9000 Gent, Belgium
- Center for Nano- and Biophotonics (NB Photonics), Ghent University, 9000 Gent, Belgium
| | - Veronique Van Speybroeck
- Center for Molecular Modeling (CMM), Ghent University, Technologiepark 903, 9052 Zwijnaarde, Belgium
| | - Pascal Van Der Voort
- Center for Ordered Materials, Organometallics and Catalysis (COMOC), Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3), 9000 Gent, Belgium
| | - Kurt Lejaeghere
- Center for Molecular Modeling (CMM), Ghent University, Technologiepark 903, 9052 Zwijnaarde, Belgium
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44
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Guńka PA, Hapka M, Hanfland M, Dranka M, Chałasiński G, Zachara J. How and Why Does Helium Permeate Nonporous Arsenolite Under High Pressure? Chemphyschem 2018; 19:857-864. [PMID: 29341365 DOI: 10.1002/cphc.201701156] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 12/06/2017] [Indexed: 11/06/2022]
Abstract
Investigations into the helium permeation of arsenolite, the cubic, molecular arsenic(III) oxide polymorph As4 O6 , were carried out to understand how and why arsenolite helium clathrate As4 O6 ⋅2 He is formed. High-pressure synchrotron X-ray diffraction experiments on arsenolite single crystals revealed that the permeation of helium into nonporous arsenolite depends on the time for which the crystal is subjected to high pressure and on the crystal history. The single crystal was totally transformed into As4 O6 ⋅2 He within 45 h under 5 GPa. After release of the pressure, arsenolite was recovered and a repeated increase in pressure up to 3 GPa led to practically instant As4 O6 ⋅2 He formation. However, when a pristine arsenolite single crystal was quickly subjected to a pressure of 13 GPa, no helium permeation was observed at all. No neon permeation was observed in analogous experiments. Quantum mechanical computations indicate that there are no specific attractive interactions between He atoms and As4 O6 molecules at the distances observed in the As4 O6 ⋅2 He crystal structure. Detailed analysis of As4 O6 molecular structure changes has shown that the introduction of He into the arsenolite crystal lattice significantly reduces molecular deformations by decreasing the anisotropy of stress exerted on the As4 O6 molecules. This effect and the pΔV term, rather than any specific As⋅⋅⋅He binding, are the driving forces for the formation As4 O6 ⋅2 He.
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Affiliation(s)
- Piotr A Guńka
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664, Warszawa, Poland
| | - Michał Hapka
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093, Warszawa, Poland
| | - Michael Hanfland
- European Synchrotron Radiation Facility, 71 avenue des Martyrs, CS 40220, 38043, Grenoble Cedex 9, France
| | - Maciej Dranka
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664, Warszawa, Poland
| | - Grzegorz Chałasiński
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093, Warszawa, Poland
| | - Janusz Zachara
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664, Warszawa, Poland
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45
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Rogal L, Bobrowski P, Körmann F, Divinski S, Stein F, Grabowski B. Computationally-driven engineering of sublattice ordering in a hexagonal AlHfScTiZr high entropy alloy. Sci Rep 2017; 7:2209. [PMID: 28526830 PMCID: PMC5438366 DOI: 10.1038/s41598-017-02385-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 04/11/2017] [Indexed: 11/24/2022] Open
Abstract
Multi-principle element alloys have enormous potential, but their exploration suffers from the tremendously large range of configurations. In the last decade such alloys have been designed with a focus on random solid solutions. Here we apply an experimentally verified, combined thermodynamic and first-principles design strategy to reverse the traditional approach and to generate a new type of hcp Al-Hf-Sc-Ti-Zr high entropy alloy with a hitherto unique structure. A phase diagram analysis narrows down the large compositional space to a well-defined set of candidates. First-principles calculations demonstrate the energetic preference of an ordered superstructure over the competing disordered solid solutions. The chief ingredient is the Al concentration, which can be tuned to achieve a D019 ordering on the hexagonal lattice. The computationally designed D019 superstructure is experimentally confirmed by transmission electron microscopy and X-ray studies. Our scheme enables the exploration of a new class of high entropy alloys.
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Affiliation(s)
- Lukasz Rogal
- Institute of Metallurgy and Materials Science of the Polish Academy of Sciences, 30-059, Krakow, Poland.
| | - Piotr Bobrowski
- Institute of Metallurgy and Materials Science of the Polish Academy of Sciences, 30-059, Krakow, Poland
| | - Fritz Körmann
- Materials Science and Engineering, Delft University of Technology, 2628, CD, Delft, Netherlands
| | - Sergiy Divinski
- Institute of Materials Physics, University of Münster, Wilhelm-Klemm-Str. 10, 48149, Münster, Germany
| | - Frank Stein
- Max-Planck-Institut für Eisenforschung GmbH D-40237, Düsseldorf, Germany
| | - Blazej Grabowski
- Max-Planck-Institut für Eisenforschung GmbH D-40237, Düsseldorf, Germany.
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Grzelak A, Gawraczyński J, Jaroń T, Somayazulu M, Derzsi M, Struzhkin V, Grochala W. Persistence of Mixed and Non-intermediate Valence in the High-Pressure Structure of Silver(I,III) Oxide, AgO: A Combined Raman, X-ray Diffraction (XRD), and Density Functional Theory (DFT) Study. Inorg Chem 2017; 56:5804-5812. [DOI: 10.1021/acs.inorgchem.7b00405] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Adam Grzelak
- Faculty of Chemistry, University of Warsaw, ul. Pasteura 1, 02-093 Warsaw, Poland
- Center of New Technologies, University of Warsaw, ul. Banacha 2C, 02-097 Warsaw, Poland
| | - Jakub Gawraczyński
- Faculty of Chemistry, University of Warsaw, ul. Pasteura 1, 02-093 Warsaw, Poland
- Center of New Technologies, University of Warsaw, ul. Banacha 2C, 02-097 Warsaw, Poland
| | - Tomasz Jaroń
- Center of New Technologies, University of Warsaw, ul. Banacha 2C, 02-097 Warsaw, Poland
- Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington, D.C. 20015, United States
| | - Maddury Somayazulu
- Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington, D.C. 20015, United States
| | - Mariana Derzsi
- Center of New Technologies, University of Warsaw, ul. Banacha 2C, 02-097 Warsaw, Poland
| | - Viktor Struzhkin
- Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington, D.C. 20015, United States
| | - Wojciech Grochala
- Center of New Technologies, University of Warsaw, ul. Banacha 2C, 02-097 Warsaw, Poland
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47
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De Vos A, Hendrickx K, Van Der Voort P, Van Speybroeck V, Lejaeghere K. Missing Linkers: An Alternative Pathway to UiO-66 Electronic Structure Engineering. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2017; 29:3006-3019. [PMID: 28413260 PMCID: PMC5390508 DOI: 10.1021/acs.chemmater.6b05444] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 03/10/2017] [Indexed: 05/10/2023]
Abstract
UiO-66 is a promising metal-organic framework for photocatalytic applications. However, the ligand-to-metal charge transfer of an excited electron is inefficient in the pristine material. Herein, we assess the influence of missing linker defects on the electronic structure of UiO-66 and discuss their ability to improve ligand-to-metal charge transfer. Using a new defect classification system, which is transparent and easily extendable, we identify the most promising photocatalysts by considering both relative stability and electronic structure. We find that the properties of UiO-66 defect structures largely depend on the coordination of the constituent nodes and that the nodes with the strongest local distortions alter the electronic structure most. Defects hence provide an alternative pathway to tune UiO-66 for photocatalytic purposes, besides linker modification and node metal substitution. In addition, the decomposition of MOF properties into node- and linker-based behavior is more generally valid, so we propose orthogonal electronic structure tuning as a paradigm in MOF design.
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Affiliation(s)
- Arthur De Vos
- Center
for Molecular Modeling (CMM), Ghent University, Technologiepark 903, 9052 Zwijnaarde, Belgium
| | - Kevin Hendrickx
- Center
for Molecular Modeling (CMM), Ghent University, Technologiepark 903, 9052 Zwijnaarde, Belgium
- Center
for Ordered Materials, Organometallics and Catalysis (COMOC), Department
of Inorganic and Physical Chemistry, Ghent
University, Krijgslaan
281 (S3), 9000 Ghent, Belgium
| | - Pascal Van Der Voort
- Center
for Ordered Materials, Organometallics and Catalysis (COMOC), Department
of Inorganic and Physical Chemistry, Ghent
University, Krijgslaan
281 (S3), 9000 Ghent, Belgium
| | - Veronique Van Speybroeck
- Center
for Molecular Modeling (CMM), Ghent University, Technologiepark 903, 9052 Zwijnaarde, Belgium
- E-mail:
| | - Kurt Lejaeghere
- Center
for Molecular Modeling (CMM), Ghent University, Technologiepark 903, 9052 Zwijnaarde, Belgium
- E-mail:
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48
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Smirnov NA. Ab initio calculations of the elastic and thermodynamic properties of gold under pressure. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:105402. [PMID: 28075332 DOI: 10.1088/1361-648x/aa58ca] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The paper presents first-principles FP-LMTO calculations on the relative stability of fcc, bcc, hcp and dhcp gold under pressure. They were done in local density approximation (LDA), as well as in generalized gradient approximation (GGA) with and without spin-orbit interaction. Phonon spectra for the considered gold structures were obtained from LDA calculations within linear response theory and the contribution of lattice vibrations to the free energy of the system was determined in quasiharmonic approximation. Our thorough adjustment of FP-LMTO internal parameters (linearization and tail energies, the MT-sphere radius) helped us to obtain results that agree well with the available experimental phase relation Dubrovinsky et al (2007 Phys. Rev. Lett. 98 045503) between fcc and hcp structures of gold under pressure. The calculations suggest that gold compressed at room temperature successively undergoes the following structural changes: [Formula: see text]. The paper also presents the calculated elastic constants of fcc, bcc and hcp Au, the principal Hugoniot and the melting curve. Calculated results were used to construct the PT-diagram which describes the relative stability of the gold structures under study up to 500 GPa.
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Affiliation(s)
- N A Smirnov
- Russian Federal Nuclear Center-Institute of Technical Physics, 456770, Snezhinsk, Russia
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49
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Thermodynamics and Equations of State of Iron to 350 GPa and 6000 K. Sci Rep 2017; 7:41863. [PMID: 28262683 PMCID: PMC5338021 DOI: 10.1038/srep41863] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 12/29/2016] [Indexed: 12/03/2022] Open
Abstract
The equations of state for solid (with bcc, fcc, and hcp structures) and liquid phases of Fe were defined via simultaneous optimization of the heat capacity, bulk moduli, thermal expansion, and volume at room and higher temperatures. The calculated triple points at the phase diagram have the following parameters: bcc–fcc–hcp is located at 7.3 GPa and 820 K, bcc–fcc–liquid at 5.2 GPa and 1998 K, and fcc–hcp–liquid at 106.5 GPa and 3787 K. At conditions near the fcc–hcp–liquid triple point, the Clapeyron slope of the fcc–liquid curve is dT/dP = 12.8 K/GPa while the slope of the hcp–liquid curve is higher (dT/dP = 13.7 K/GPa). Therefore, the hcp–liquid curve overlaps the metastable fcc–liquid curve at pressures of about 160 GPa. At high-pressure conditions, the metastable bcc–hcp curve is located inside the fcc-Fe or liquid stability field. The density, adiabatic bulk modulus and P-wave velocity of liquid Fe calculated up to 328.9 GPa at adiabatic temperature conditions started from 5882 K (outer/inner core boundary) were compared to the PREM seismological model. We determined the density deficit of hcp-Fe at the inner core boundary (T = 5882 K and P = 328.9 GPa) to be 4.4%.
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50
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Severin J, Jund P. Thermal conductivity calculation in anisotropic crystals by molecular dynamics: Application to α-Fe 2O 3. J Chem Phys 2017; 146:054505. [PMID: 28178828 DOI: 10.1063/1.4974933] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
In this work, we aim to study the thermal properties of materials using classical molecular dynamics simulations and specialized numerical methods. We focus primarily on the thermal conductivity κ using non-equilibrium molecular dynamics (NEMD) to study the response of a crystalline solid, namely hematite (α-Fe2O3), to an imposed heat flux as is the case in real life applications. We present a methodology for the calculation of κ as well as an adapted potential for hematite. Taking into account the size of the simulation box, we show that not only the longitudinal size (in the direction of the heat flux) but also the transverse size plays a role in the determination of κ and should be converged properly in order to have reliable results. Moreover we propose a comparison of thermal conductivity calculations in two different crystallographic directions to highlight the spatial anisotropy and we investigate the non-linear temperature behavior typically observed in NEMD methods.
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Affiliation(s)
- Jonathan Severin
- UMR 5253 CNRS-UM-ENSCM, Institut Charles Gerhardt Montpellier, Place E. Bataillon CC1506, 34095 Montpellier, France
| | - Philippe Jund
- UMR 5253 CNRS-UM-ENSCM, Institut Charles Gerhardt Montpellier, Place E. Bataillon CC1506, 34095 Montpellier, France
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