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Composition/structure directed search for new chalcogenide compounds
Authors:
Alon Hever,
Ohad Levy,
Stefano Curtarolo,
Amir Natan
Abstract:
This work presents a simple scheme for finding new crystalline compounds by adapting structure types from neighbor atoms compounds. The approach is demonstrated for the selenide and sulfide families of binary compounds. It predicts ten new compounds that are not currently included in the inorganic crystal structure database (ICSD). The compounds primarily originated from a small search domain that…
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This work presents a simple scheme for finding new crystalline compounds by adapting structure types from neighbor atoms compounds. The approach is demonstrated for the selenide and sulfide families of binary compounds. It predicts ten new compounds that are not currently included in the inorganic crystal structure database (ICSD). The compounds primarily originated from a small search domain that includes near neighbors. Comparison with extended searches that include structures from binary systems of more remote atoms in the periodic table demonstrate the relative efficiency of near neighbor screening. This points at the possibility of using similar directed searches as a heuristic rule for efficiently finding new stable compounds in additional compound families.
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Submitted 11 December, 2025;
originally announced December 2025.
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aflow++: a C++ framework for autonomous materials design
Authors:
C. Oses,
M. Esters,
D. Hicks,
S. Divilov,
H. Eckert,
R. Friedrich,
M. J. Mehl,
A. Smolyanyuk,
X. Campilongo,
A. van de Walle,
J Schroers,
A. G. Kusne,
I. Takeuchi,
E. Zurek,
M. Buongiorno Nardelli,
M. Fornari,
Y. Lederer,
O. Levy,
C. Toher,
S. Curtarolo
Abstract:
The realization of novel technological opportunities given by computational and autonomous materials design requires efficient and effective frameworks. For more than two decades, aflow++ (Automatic-Flow Framework for Materials Discovery) has provided an interconnected collection of algorithms and workflows to address this challenge. This article contains an overview of the software and some of it…
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The realization of novel technological opportunities given by computational and autonomous materials design requires efficient and effective frameworks. For more than two decades, aflow++ (Automatic-Flow Framework for Materials Discovery) has provided an interconnected collection of algorithms and workflows to address this challenge. This article contains an overview of the software and some of its most heavily-used functionalities, including algorithmic details, standards, and examples. Key thrusts are highlighted: the calculation of structural, electronic, thermodynamic, and thermomechanical properties in addition to the modeling of complex materials, such as high-entropy ceramics and bulk metallic glasses. The aflow++ software prioritizes interoperability, minimizing the number of independent parameters and tolerances. It ensures consistency of results across property sets - facilitating machine learning studies. The software also features various validation schemes, offering real-time quality assurance for data generated in a high-throughput fashion. Altogether, these considerations contribute to the development of large and reliable materials databases that can ultimately deliver future materials systems
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Submitted 5 August, 2022;
originally announced August 2022.
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The AFLOW Library of Crystallographic Prototypes: Part 3
Authors:
David Hicks,
Michael J. Mehl,
Marco Esters,
Corey Oses,
Ohad Levy,
Gus L. W. Hart,
Cormac Toher,
Stefano Curtarolo
Abstract:
The AFLOW Library of Crystallographic Prototypes has been extended to include a total of 1,100 common crystal structural prototypes (510 new ones with Part 3), comprising all of the inorganic crystal structures defined in the seven-volume Strukturbericht series published in Germany from 1937 through 1943. We cover a history of the Strukturbericht designation system, the evolution of the system ove…
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The AFLOW Library of Crystallographic Prototypes has been extended to include a total of 1,100 common crystal structural prototypes (510 new ones with Part 3), comprising all of the inorganic crystal structures defined in the seven-volume Strukturbericht series published in Germany from 1937 through 1943. We cover a history of the Strukturbericht designation system, the evolution of the system over time, and the first comprehensive index of inorganic Strukturbericht designations ever published.
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Submitted 10 December, 2020;
originally announced December 2020.
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AFLOW-XtalFinder: a reliable choice to identify crystalline prototypes
Authors:
David Hicks,
Cormac Toher,
Denise C. Ford,
Frisco Rose,
Carlo De Santo,
Ohad Levy,
Michael J. Mehl,
Stefano Curtarolo
Abstract:
The accelerated growth rate of repository entries in crystallographic databases makes it arduous to identify and classify their prototype structures. The open-source AFLOW-XtalFinder package was developed to solve this problem. It symbolically maps structures into standard designations following the AFLOW Prototype Encyclopedia and calculates the internal degrees of freedom consistent with the Int…
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The accelerated growth rate of repository entries in crystallographic databases makes it arduous to identify and classify their prototype structures. The open-source AFLOW-XtalFinder package was developed to solve this problem. It symbolically maps structures into standard designations following the AFLOW Prototype Encyclopedia and calculates the internal degrees of freedom consistent with the International Tables for Crystallography. To ensure uniqueness, structures are analyzed and compared via symmetry, local atomic geometries, and crystal mapping techniques, simultaneously grouping them by similarity. The software i. distinguishes distinct crystal prototypes and atom decorations, ii. determines equivalent spin configurations, iii. reveals compounds with similar properties, and iv. guides the discovery of unexplored materials. The operations are accessible through a Python module ready for workflows, and through command line syntax. All the 4+ million compounds in the AFLOW.org repositories are mapped to their ideal prototype, allowing users to search database entries via symbolic structure-type. Furthermore, 15,000 unique structures - sorted by prevalence - are extracted from the AFLOW-ICSD catalog to serve as future prototypes in the Encyclopedia.
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Submitted 8 October, 2020;
originally announced October 2020.
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The AFLOW Library of Crystallographic Prototypes: Part 2
Authors:
David Hicks,
Michael J. Mehl,
Eric Gossett,
Cormac Toher,
Ohad Levy,
Robert M. Hanson,
Gus Hart,
Stefano Curtarolo
Abstract:
Materials discovery via high-throughput methods relies on the availability of structural prototypes, which are generally decorated with varying combinations of elements to produce potential new materials. To facilitate the automatic generation of these materials, we developed $\textit{The AFLOW Library of Crystallographic Prototypes}$ $\unicode{x2014}$ a collection of crystal prototypes that can b…
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Materials discovery via high-throughput methods relies on the availability of structural prototypes, which are generally decorated with varying combinations of elements to produce potential new materials. To facilitate the automatic generation of these materials, we developed $\textit{The AFLOW Library of Crystallographic Prototypes}$ $\unicode{x2014}$ a collection of crystal prototypes that can be rapidly decorated using the AFLOW software. Part 2 of this work introduces an additional 302 crystal structure prototypes, including at least one from each of the 138 space groups not included in Part 1. Combined with Part 1, the entire library consists of 590 unique crystallographic prototypes covering all 230 space groups. We also present discussions of enantiomorphic space groups, Wigner-Seitz cells, the two-dimensional plane groups, and the various different space group notations used throughout crystallography. All structures $\unicode{x2014}$ from both Part 1 and Part 2 $\unicode{x2014}$ are listed in the web version of the library available at aflow.org/CrystalDatabase.
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Submitted 20 June, 2018;
originally announced June 2018.
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AFLOW-CHULL: Cloud-oriented platform for autonomous phase stability analysis
Authors:
Corey Oses,
Eric Gossett,
David Hicks,
Frisco Rose,
Michael J. Mehl,
Eric Perim,
Ichiro Takeuchi,
Stefano Sanvito,
Matthias Scheffler,
Yoav Lederer,
Ohad Levy,
Cormac Toher,
Stefano Curtarolo
Abstract:
$\textit{A priori}$ prediction of phase stability of materials is a challenging practice, requiring knowledge of all energetically-competing structures at formation conditions. Large materials repositories $\unicode{x2014}$ housing properties of both experimental and hypothetical compounds $\unicode{x2014}$ offer a path to prediction through the construction of informatics-based, $\textit{ab-initi…
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$\textit{A priori}$ prediction of phase stability of materials is a challenging practice, requiring knowledge of all energetically-competing structures at formation conditions. Large materials repositories $\unicode{x2014}$ housing properties of both experimental and hypothetical compounds $\unicode{x2014}$ offer a path to prediction through the construction of informatics-based, $\textit{ab-initio}$ phase diagrams. However, limited access to relevant data and software infrastructure has rendered thermodynamic characterizations largely peripheral, despite their continued success in dictating synthesizability. Herein, a new module is presented for autonomous thermodynamic stability analysis implemented within the open-source, $\textit{ab-initio}$ framework AFLOW. Powered by the AFLUX Search-API, AFLOW-CHULL leverages data of more than 1.8 million compounds currently characterized in the AFLOW.org repository and can be employed locally from any UNIX-like computer. The module integrates a range of functionality: the identification of stable phases and equivalent structures, phase coexistence, measures for robust stability, and determination of decomposition reactions. As a proof-of-concept, thorough thermodynamic characterizations have been performed for more than 1,300 binary and ternary systems, enabling the identification of several candidate phases for synthesis based on their relative stability criterion $\unicode{x2014}$ including 18 promising $C15_{b}$-type structures and two half-Heuslers. In addition to a full report included herein, an interactive, online web application has been developed showcasing the results of the analysis, and is located at aflow.org/aflow-chull.
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Submitted 18 June, 2018;
originally announced June 2018.
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AFLOW-SYM: Platform for the complete, automatic and self-consistent symmetry analysis of crystals
Authors:
David Hicks,
Corey Oses,
Eric Gossett,
Geena Gomez,
Richard H. Taylor,
Cormac Toher,
Michael J. Mehl,
Ohad Levy,
Stefano Curtarolo
Abstract:
Determination of the symmetry profile of structures is a persistent challenge in materials science. Results often vary amongst standard packages, hindering autonomous materials development by requiring continuous user attention and educated guesses. Here, we present a robust procedure for evaluating the complete suite of symmetry properties, featuring various representations for the point-, factor…
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Determination of the symmetry profile of structures is a persistent challenge in materials science. Results often vary amongst standard packages, hindering autonomous materials development by requiring continuous user attention and educated guesses. Here, we present a robust procedure for evaluating the complete suite of symmetry properties, featuring various representations for the point-, factor-, space groups, site symmetries, and Wyckoff positions. The protocol determines a system-specific mapping tolerance that yields symmetry operations entirely commensurate with fundamental crystallographic principles. The self consistent tolerance characterizes the effective spatial resolution of the reported atomic positions. The approach is compared with the most used programs and is successfully validated against the space group information provided for over 54,000 entries in the Inorganic Crystal Structure Database. Subsequently, a complete symmetry analysis is applied to all 1.7$+$ million entries of the AFLOW data repository. The AFLOW-SYM package has been implemented in, and made available for, public use through the automated, $\textit{ab-initio}$ framework AFLOW.
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Submitted 22 February, 2018;
originally announced February 2018.
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The AFLOW Fleet for Materials Discovery
Authors:
Cormac Toher,
Corey Oses,
David Hicks,
Eric Gossett,
Frisco Rose,
Pinku Nath,
Demet Usanmaz,
Denise C. Ford,
Eric Perim,
Camilo E. Calderon,
Jose J. Plata,
Yoav Lederer,
Michal Jahnátek,
Wahyu Setyawan,
Shidong Wang,
Junkai Xue,
Kevin Rasch,
Roman V. Chepulskii,
Richard H. Taylor,
Geena Gomez,
Harvey Shi,
Andrew R. Supka,
Rabih Al Rahal Al Orabi,
Priya Gopal,
Frank T. Cerasoli
, et al. (26 additional authors not shown)
Abstract:
The traditional paradigm for materials discovery has been recently expanded to incorporate substantial data driven research. With the intent to accelerate the development and the deployment of new technologies, the AFLOW Fleet for computational materials design automates high-throughput first principles calculations, and provides tools for data verification and dissemination for a broad community…
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The traditional paradigm for materials discovery has been recently expanded to incorporate substantial data driven research. With the intent to accelerate the development and the deployment of new technologies, the AFLOW Fleet for computational materials design automates high-throughput first principles calculations, and provides tools for data verification and dissemination for a broad community of users. AFLOW incorporates different computational modules to robustly determine thermodynamic stability, electronic band structures, vibrational dispersions, thermo-mechanical properties and more. The AFLOW data repository is publicly accessible online at aflow.org, with more than 1.7 million materials entries and a panoply of queryable computed properties. Tools to programmatically search and process the data, as well as to perform online machine learning predictions, are also available.
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Submitted 1 December, 2017;
originally announced December 2017.
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The structure and composition statistics of 6A binary and ternary crystalline materials
Authors:
Alon Hever,
Corey Oses,
Stefano Curtarolo,
Ohad Levy,
Amir Natan
Abstract:
The fundamental principles underlying the arrangement of elements into solid compounds with an enormous variety of crystal structures are still largely unknown. This study presents a general overview of the structure types appearing in an important subset of the solid compounds, i.e., binary and ternary compounds of the 6A column oxides, sulfides and selenides. It contains an analysis of these com…
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The fundamental principles underlying the arrangement of elements into solid compounds with an enormous variety of crystal structures are still largely unknown. This study presents a general overview of the structure types appearing in an important subset of the solid compounds, i.e., binary and ternary compounds of the 6A column oxides, sulfides and selenides. It contains an analysis of these compounds, including the prevalence of various structure types, their symmetry properties, compositions, stoichiometries and unit cell sizes. It is found that these compound families include preferred stoichiometries and structure types that may reflect both their specific chemistry and research bias in the available empirical data. Identification of non-overlapping gaps and missing stoichiometries in these structure populations may be used as guidance in the search for new materials.
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Submitted 8 December, 2017; v1 submitted 13 March, 2017;
originally announced March 2017.
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Combining the AFLOW GIBBS and Elastic Libraries for efficiently and robustly screening thermo-mechanical properties of solids
Authors:
Cormac Toher,
Corey Oses,
Jose J. Plata,
David Hicks,
Frisco Rose,
Ohad Levy,
Maarten de Jong,
Mark Asta,
Marco Fornari,
Marco Buongiorno Nardelli,
Stefano Curtarolo
Abstract:
Thorough characterization of the thermo-mechanical properties of materials requires difficult and time-consuming experiments. This severely limits the availability of data and it is one of the main obstacles for the development of effective accelerated materials design strategies. The rapid screening of new potential systems requires highly integrated, sophisticated and robust computational approa…
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Thorough characterization of the thermo-mechanical properties of materials requires difficult and time-consuming experiments. This severely limits the availability of data and it is one of the main obstacles for the development of effective accelerated materials design strategies. The rapid screening of new potential systems requires highly integrated, sophisticated and robust computational approaches. We tackled the challenge by surveying more than 3,000 crystalline solids within the AFLOW framework with the newly developed "Automatic Elasticity Library" combined with the previously implemented GIBBS method. The first extracts the mechanical properties from automatic self-consistent stress-strain calculations, while the latter employs those mechanical properties to evaluate the thermodynamics within the Debye model. The new thermo-elastic library is benchmarked against a set of 74 experimentally characterized systems to pinpoint a robust computational methodology for the evaluation of bulk and shear moduli, Poisson ratios, Debye temperatures, Grüneisen parameters, and thermal conductivities of a wide variety of materials. The effect of different choices of equations of state is examined and the optimum combination of properties for the Leibfried-Schlömann prediction of thermal conductivity is identified, leading to improved agreement with experimental results than the GIBBS-only approach.
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Submitted 15 March, 2017; v1 submitted 17 November, 2016;
originally announced November 2016.
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The molybdenum-titanium phase diagram evaluated from ab-initio calculations
Authors:
S. Barzilai,
C. Toher,
S. Curtarolo,
O. Levy
Abstract:
The design of next generation β-type titanium implants requires detailed knowledge of the relevant stable and metastable phases at temperatures where metallurgical heat treatments can be performed. Recently, a standard specification for surgical implant applications was established for Mo-Ti alloys. However, the thermodynamic properties of this binary system are not well known and two conflicting…
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The design of next generation β-type titanium implants requires detailed knowledge of the relevant stable and metastable phases at temperatures where metallurgical heat treatments can be performed. Recently, a standard specification for surgical implant applications was established for Mo-Ti alloys. However, the thermodynamic properties of this binary system are not well known and two conflicting descriptions of the β-phase stability have been presented in the literature. In this study, we use ab-initio calculations to investigate the Mo-Ti phase diagram. These calculations predict that the β-phase is stable over a wide concentration range, in qualitative agreement with one of the reported phase diagrams. In addition, they predict stoichiometric compounds, stable at temperatures below 3000C, which have not yet been detected by experiments. The resulting solvus, which defines the transition to the β-phase solid solution, therefore occurs at lower temperatures and is more complex than previously anticipated.
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Submitted 6 October, 2016;
originally announced October 2016.
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Addressing the lattice stability puzzle in the computational determination of intermetallic phase diagrams
Authors:
Shmuel Barzilai,
Cormac Toher,
Stefano Curtarolo,
Ohad Levy
Abstract:
The evaluation of phase stabilities of unstable elemental phases is a long-standing problem in the computational assessment of phase diagrams. Here we tackle this problem by explicitly calculating phase diagrams of intermetallic systems where its effect should be most conspicuous, binary systems of titanium with bcc transition metals (Mo, Nb, Ta and V). Two types of phase diagrams are constructed:…
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The evaluation of phase stabilities of unstable elemental phases is a long-standing problem in the computational assessment of phase diagrams. Here we tackle this problem by explicitly calculating phase diagrams of intermetallic systems where its effect should be most conspicuous, binary systems of titanium with bcc transition metals (Mo, Nb, Ta and V). Two types of phase diagrams are constructed: one based on the lattice stabilities extracted from empirical data, and the other using the lattice stabilities computed from first principles. It is shown that the phase diagrams obtained using the empirical values contain clear contradictions with the experimental phase diagrams at the well known limits of low or high temperatures. Realistic phase diagrams, with a good agreement with the experimental observations, are achieved only when the computed lattice stability values are used. At intermediate temperatures, the computed phase diagrams resolve the controversy regarding the shape of the solvus in these systems, predicting a complex structure with a eutectoid transition and a miscibility gap between two bcc phases.
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Submitted 16 September, 2016;
originally announced September 2016.
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The AFLOW Library of Crystallographic Prototypes
Authors:
Michael J. Mehl,
David Hicks,
Cormac Toher,
Ohad Levy,
Robert M. Hanson,
Gus Hart,
Stefano Curtarolo
Abstract:
An easily available resource of common crystal structures is essential for researchers, teachers, and students. For many years this was provided by the U.S. Naval Research Laboratory's $Crystal\ Lattice\ Structures$ web page, which contained nearly 300 crystal structures, including a majority of those which were given $Strukturbericht$ designations. This article presents the updated version of the…
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An easily available resource of common crystal structures is essential for researchers, teachers, and students. For many years this was provided by the U.S. Naval Research Laboratory's $Crystal\ Lattice\ Structures$ web page, which contained nearly 300 crystal structures, including a majority of those which were given $Strukturbericht$ designations. This article presents the updated version of the database, now including 288 standardized structures in 92 space groups. Similar to what was available on the web page before, we present a complete description of each structure, including the formulas for the primitive vectors, all of the basis vectors, and the AFLOW commands to generate the standardied cells. We also present a brief discussion of crystal systems, space groups, primitive and conventional lattices, Wyckoff positions, Pearson symbols and $Strukturbericht$ designations.
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Submitted 7 December, 2016; v1 submitted 8 July, 2016;
originally announced July 2016.
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Spectral descriptors for bulk metallic glasses based on the thermodynamics of competing crystalline phases
Authors:
Eric Perim,
Dongwoo Lee,
Yanhui Liu,
Cormac Toher,
Pan Gong,
Yanglin Li,
W. Neal Simmons,
Ohad Levy,
Joost J. Vlassak,
Jan Schroers,
Stefano Curtarolo
Abstract:
Metallic glasses have attracted considerable interest in recent years due to their unique combination of superb properties and processability. Predicting bulk metallic glass formers from known parameters remains a challenge and the search for new systems is still performed by trial and error. It has been speculated that some sort of "confusion" during crystallization of the crystalline phases comp…
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Metallic glasses have attracted considerable interest in recent years due to their unique combination of superb properties and processability. Predicting bulk metallic glass formers from known parameters remains a challenge and the search for new systems is still performed by trial and error. It has been speculated that some sort of "confusion" during crystallization of the crystalline phases competing with glass formation could play a key role. Here, we propose a heuristic descriptor quantifying confusion and demonstrate its validity by detailed experiments on two well-known glass forming alloy systems. With the insight provided by these results, we develop a robust model for predicting glass formation ability based on the spectral decomposition of geometrical and energetic features of crystalline phases calculated ab-initio in the AFLOW high throughput framework. Our findings indicate that the formation of metallic glass phases could be a much more common phenomenon than currently estimated, with more than 17% of binary alloy systems being potential glass formers. Our approach is capable of pinpointing favorable compositions, overcoming a major bottleneck hindering the discovery of new materials. Hence, it is demonstrated that smart descriptors, based solely on the energetics and structure of competing crystalline phases calculated from first-principles and available in online databases, others the sought-after key for accelerated discovery of novel metallic glasses.
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Submitted 16 July, 2016; v1 submitted 3 June, 2016;
originally announced June 2016.
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Predicting Bulk Metallic Glass Forming Ability with the Thermodynamic Density of Competing Crystalline States
Authors:
Eric Perim,
Dongwoo Lee,
Yanhui Liu,
Cormac Toher,
Pan Gong,
Yanglin Li,
W. Neal Simmons,
Ohad Levy,
Joost Vlassak,
Jan Schroers,
Stefano Curtarolo
Abstract:
Despite two decades of studies, the formation of metallic glasses, very promising systems for industrial applications, still remains mostly unexplained. This lack of knowledge hinders the search for new systems, still performed with combinatorial trial and error. In the past, it was speculated that some sort of "confusion" during crystallization could play a key role during their formation. In thi…
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Despite two decades of studies, the formation of metallic glasses, very promising systems for industrial applications, still remains mostly unexplained. This lack of knowledge hinders the search for new systems, still performed with combinatorial trial and error. In the past, it was speculated that some sort of "confusion" during crystallization could play a key role during their formation. In this article, we propose a heuristic descriptor quantifying such confusion. It is based on the "thermodynamic density of competing crystalline states", parameterized from high-throughput ab-initio calculations. The existence of highly enthalpy-degenerate but geometrically-different phases frustrates the crystallization process and promotes glass formation. Two test beds are considered. A good and a bad glass-former, CuZr and NiZr, are experimentally characterized with high-throughput synthesis. The experimental results corroborate the capability of the heuristic descriptor in predicting glass forming ability through the compositional space. Our analysis is expected to deepen the understanding of the underlying mechanisms and to accelerate the discovery of novel metallic glasses.
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Submitted 1 February, 2016; v1 submitted 29 January, 2016;
originally announced January 2016.
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The AFLOW Standard for High-Throughput Materials Science Calculations
Authors:
Camilo E. Calderon,
Jose J. Plata,
Cormac Toher,
Corey Oses,
Ohad Levy,
Marco Fornari,
Amir Natan,
Michael J. Mehl,
Gus Hart,
Marco Buongiorno Nardelli,
Stefano Curtarolo
Abstract:
The Automatic-Flow ( AFLOW ) standard for the high-throughput construction of materials science electronic structure databases is described. Electronic structure calculations of solid state materials depend on a large number of parameters which must be understood by researchers, and must be reported by originators to ensure reproducibility and enable collaborative database expansion. We therefore…
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The Automatic-Flow ( AFLOW ) standard for the high-throughput construction of materials science electronic structure databases is described. Electronic structure calculations of solid state materials depend on a large number of parameters which must be understood by researchers, and must be reported by originators to ensure reproducibility and enable collaborative database expansion. We therefore describe standard parameter values for k-point grid density, basis set plane wave kinetic energy cut-off, exchange-correlation functionals, pseudopotentials, DFT+U parameters, and convergence criteria used in AFLOW calculations.
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Submitted 31 May, 2015;
originally announced June 2015.
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Thermodynamic properties of titanium from ab-initio calculations
Authors:
Uri Argaman,
Eitan Eidelstein,
Ohad Levy,
Guy Makov
Abstract:
The lattice parameters, lattice stability and phonon dispersion curves of five proposed phases of Ti: alpha, beta, gamma, delta and omega are investigated within DFT. It is found that the sequence of high pressure phases at zero temperature is alpha, omega, gamma, delta and beta with the delta and beta phases becoming degenerate at high pressure. However, the gamma phase may be unstable as is refl…
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The lattice parameters, lattice stability and phonon dispersion curves of five proposed phases of Ti: alpha, beta, gamma, delta and omega are investigated within DFT. It is found that the sequence of high pressure phases at zero temperature is alpha, omega, gamma, delta and beta with the delta and beta phases becoming degenerate at high pressure. However, the gamma phase may be unstable as is reflected by the existence of imaginary values in the phonon spectra. The results of the DFT calculations are employed to estimate the entropy and free energies of the alpha and omega phases. It is found that converged phonon calculations lead to an entropy difference which is much smaller than previous estimates, and a much steeper alpha-omega phase transition line.
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Submitted 22 December, 2014;
originally announced December 2014.
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High-Throughput Computational Screening of thermal conductivity, Debye temperature and Grüneisen parameter using a quasi-harmonic Debye Model
Authors:
Cormac Toher,
Jose J. Plata,
Ohad Levy,
Maarten de Jong,
Mark Asta,
Marco Buongiorno Nardelli,
Stefano Curtarolo
Abstract:
The quasi-harmonic Debye approximation has been implemented within the AFLOW and Materials Project frameworks for high-throughput computational science (Automatic Gibbs Library, AGL), in order to calculate thermal properties such as the Debye temperature and the thermal conductivity of materials. We demonstrate that the AGL method, which is significantly cheaper computationally compared to the ful…
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The quasi-harmonic Debye approximation has been implemented within the AFLOW and Materials Project frameworks for high-throughput computational science (Automatic Gibbs Library, AGL), in order to calculate thermal properties such as the Debye temperature and the thermal conductivity of materials. We demonstrate that the AGL method, which is significantly cheaper computationally compared to the fully ab initio approach, can reliably predict the ordinal ranking of the thermal conductivity for several different classes of semiconductor materials. We also find that for the set of 182 materials investigated in this work the Debye temperature, calculated with the AGL, is often a better predictor of the ordinal ranking of the experimental thermal conductivities than the calculated thermal conductivity. The Debye temperature is thus a potential descriptor for high-throughput screening of the thermal properties of materials.
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Submitted 14 October, 2014; v1 submitted 29 July, 2014;
originally announced July 2014.
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A RESTful API for exchanging Materials Data in the AFLOWLIB.org consortium
Authors:
Richard H. Taylor,
Frisco Rose,
Cormac Toher,
Ohad Levy,
Marco Buongiorno Nardelli,
Stefano Curtarolo
Abstract:
The continued advancement of science depends on shared and reproducible data. In the field of computational materials science and rational materials design this entails the construction of large open databases of materials properties. To this end, an Application Program Interface (API) following REST principles is introduced for the AFLOWLIB.org materials data repositories consortium. AUIDs (Aflow…
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The continued advancement of science depends on shared and reproducible data. In the field of computational materials science and rational materials design this entails the construction of large open databases of materials properties. To this end, an Application Program Interface (API) following REST principles is introduced for the AFLOWLIB.org materials data repositories consortium. AUIDs (Aflowlib Unique IDentifier) and AURLs (Aflowlib Uniform Resource locator) are assigned to the database resources according to a well-defined protocol described herein, which enables the client to access, through appropriate queries, the desired data for post-processing. This introduces a new level of openness into the AFLOWLIB repository, allowing the community to construct high-level work-flows and tools exploiting its rich data set of calculated structural, thermodynamic, and electronic properties. Furthermore, federating these tools would open the door to collaborative investigation of the data by an unprecedented extended community of users to accelerate the advancement of computational materials design and development.
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Submitted 2 May, 2014; v1 submitted 11 March, 2014;
originally announced March 2014.
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Stable ordered structures of binary technetium alloys from first principles
Authors:
Ohad Levy,
Junkai Xue,
Shidong Wang,
Gus L. W. Hart,
Stefano Curtarolo
Abstract:
Technetium, element 43, is the only radioactive transition metal. It occurs naturally on earth in only trace amounts. Experimental investigation of its possible compounds is thus inherently difficult and limited. Half of the Tc-transition-metal systems (14 out of 28) are reported to be phase separating or lack experimental data. Using high-throughput first-principles calculations, we present a com…
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Technetium, element 43, is the only radioactive transition metal. It occurs naturally on earth in only trace amounts. Experimental investigation of its possible compounds is thus inherently difficult and limited. Half of the Tc-transition-metal systems (14 out of 28) are reported to be phase separating or lack experimental data. Using high-throughput first-principles calculations, we present a comprehensive investigation of the binary alloys of technetium with the transition metals. The calculations predict stable, ordered structures in nine of these 14 binary systems. They also predict additional compounds in all nine known compound-forming systems and in two of the five systems reported with disordered \c{hi} or σ phases. These results accentuate the incompleteness of the current knowledge of technetium alloys and should guide experimental studies to obtain accurate structural information on potential compounds, obviating some of the difficulties associated with such work.
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Submitted 26 August, 2013;
originally announced August 2013.
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AFLOW: An automatic framework for high-throughput materials discovery
Authors:
Stefano Curtarolo,
Wahyu Setyawan,
Gus L. W. Hart,
Michal Jahnatek,
Roman V. Chepulskii,
Richard H. Taylor,
Shidong Wang,
Junkai Xue,
Kesong Yang,
Ohad Levy,
Michael J. Mehl,
Harold T. Stokes,
Denis O. Demchenko,
Dane Morgan
Abstract:
Recent advances in computational materials science present novel opportunities for structure discovery and optimization, including uncovering of unsuspected compounds and metastable structures, electronic structure, surface, and nano-particle properties. The practical realization of these opportunities requires systematic generation and classification of the relevant computational data by high-thr…
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Recent advances in computational materials science present novel opportunities for structure discovery and optimization, including uncovering of unsuspected compounds and metastable structures, electronic structure, surface, and nano-particle properties. The practical realization of these opportunities requires systematic generation and classification of the relevant computational data by high-throughput methods. In this paper we present Aflow (Automatic Flow), a software framework for high-throughput calculation of crystal structure properties of alloys, intermetallics and inorganic compounds. The Aflow software is available for the scientific community on the website of the materials research consortium, aflowlib.org. Its geometric and electronic structure analysis and manipulation tools are additionally available for online operation at the same website. The combination of automatic methods and user online interfaces provide a powerful tool for efficient quantum computational materials discovery and characterization.
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Submitted 26 August, 2013;
originally announced August 2013.
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A high-throughput ab initio review of platinum-group alloy systems
Authors:
Gus L. W. Hart,
Stefano Curtarolo,
Thaddeus B. Massalski,
Ohad Levy
Abstract:
We report a comprehensive study of the binary systems of the platinum group metals with the transition metals, using high-throughput first-principles calculations. These computations predict stability of new compounds in 38 binary systems where no compounds have been reported in the literature experimentally, and a few dozen of as yet unreported compounds in additional systems. Our calculations al…
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We report a comprehensive study of the binary systems of the platinum group metals with the transition metals, using high-throughput first-principles calculations. These computations predict stability of new compounds in 38 binary systems where no compounds have been reported in the literature experimentally, and a few dozen of as yet unreported compounds in additional systems. Our calculations also identify stable structures at compound compositions that have been previously reported without detailed structural data and indicate that some experimentally reported compounds may actually be unstable at low temperatures. With these results we construct enhanced structure maps for the binary alloys of platinum group metals. These are much more complete, systematic and predictive than those based on empirical results alone.
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Submitted 21 February, 2014; v1 submitted 20 August, 2013;
originally announced August 2013.
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Structure maps for hcp metals from first principles calculations
Authors:
Ohad Levy,
Gus Hart,
Stefano Curtarolo
Abstract:
The ability to predict the existence and crystal type of ordered structures of materials from their components is a major challenge of current materials research. Empirical methods use experimental data to construct structure maps and make predictions based on clustering of simple physical parameters. Their usefulness depends on the availability of reliable data over the entire parameter space.…
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The ability to predict the existence and crystal type of ordered structures of materials from their components is a major challenge of current materials research. Empirical methods use experimental data to construct structure maps and make predictions based on clustering of simple physical parameters. Their usefulness depends on the availability of reliable data over the entire parameter space. Recent development of high throughput methods opens the possibility to enhance these empirical structure maps by {\it ab initio} calculations in regions of the parameter space where the experimental evidence is lacking or not well characterized. In this paper we construct enhanced maps for the binary alloys of hcp metals, where the experimental data leaves large regions of poorly characterized systems believed to be phase-separating. In these enhanced maps, the clusters of non-compound forming systems are much smaller than indicated by the empirical results alone.
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Submitted 14 February, 2010;
originally announced February 2010.
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Hafnium binary alloys from experiments and first principles
Authors:
Ohad Levy,
Gus L. W. Hart,
Stefano Curtarolo
Abstract:
Despite the increasing importance of hafnium in numerous technological applications, experimental and computational data on its binary alloys is sparse. In particular, data is scant on those binary systems believed to be phase separating. We performed a comprehensive study of 44 hafnium binary systems with alkali metals, alkaline earths, transition metals and metals, using high-throughput first…
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Despite the increasing importance of hafnium in numerous technological applications, experimental and computational data on its binary alloys is sparse. In particular, data is scant on those binary systems believed to be phase separating. We performed a comprehensive study of 44 hafnium binary systems with alkali metals, alkaline earths, transition metals and metals, using high-throughput first principles calculations. These computations predict novel unsuspected compounds in six binary systems previously believed to be phase separating They also predict a few unreported compounds in additional systems and indicate that some reported compounds may actually be unstable at low temperatures. We report the results for the following systems: AgHf, AlHf, AuHf, BaHf*, BeHf, BiHf, CaHf*, CdHf, CoHf, CrHf, CuHf, FeHf, GaHf, HfHg, HfIn, HfIr, HfK*, HfLa*, HfLi*, HfMg, HfMn, HfMo, HfNa*, HfNb*, HfNi, HfOs, HfPb, HfPd, HfPt, HfRe, HfRh, HfRu, HfSc, HfSn, HfSr*, HfTa*, HfTc, HfTi, HfTl, HfV*, HfW, HfY*, HfZn, and HfZr. (* = systems in which the ab initio method predicts that no compounds are stable).
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Submitted 29 July, 2009;
originally announced July 2009.