Algorithm Development in Materials Science and Engineering: Interatomic Potential Developments and Atomistic Modeling I
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Integrated Computational Materials Engineering Committee, TMS: Phase Transformations Committee, TMS: Computational Materials Science and Engineering Committee
Program Organizers: Mohsen Asle Zaeem, Colorado School of Mines; Garritt Tucker, Colorado School of Mines; Charudatta Phatak, Argonne National Laboratory; Bryan Wong, University of California, Riverside; Mikhail Mendelev, NASA ARC; Bryce Meredig, Travertine Labs LLC; Ebrahim Asadi, University of Memphis; Francesca Tavazza, National Institute of Standards and Technology
Monday 2:30 PM
February 24, 2020
Room: 31C
Location: San Diego Convention Ctr
Session Chair: Mikhail Mendelev, NASA ARC; Ebrahim Asadi, University of Memphis
2:30 PM Invited
Advancing Methods for Atomic-scale Modeling of Heterogeneous Systems: Susan Sinnott1; 1Pennsylvania State University
Interatomic interactions within heterogeneous systems are challenging to model with high fidelity at the atomic scale across significant length scales. This presentation describes recent developments of third-generation charge optimized many-body (COMB3) potentials to enable water interactions with metal and metal alloys. Both clusters and surfaces are considered and the roles of adsorbed hydroxide and oxygen species on water interactions are quantified.
3:00 PM
The ReaxFF Force Field- application Overview and New Directions in Accelerated Dynamics, Ferroelectric Materials and Treatment of Explicit Electrons: Adrianus Van Duin1; Yun Kyung Shin1; 1Penn State
The ReaxFF method provides a highly transferable simulation method for atomistic scale simulations on chemical reactions. It combines concepts of bond-order based potentials with a polarizable charge distribution. Since its development for hydrocarbons in 2001, we have found that this concept is transferable to elements all across the periodic table, including all first row elements including biomolecules, metals, ceramics and ionic materials. For all these molecules and materials we have demonstrated that ReaxFF can accurately reproduce quantum mechanics-based structures, reaction energies and reaction barriers, enabling the method to predict reaction kinetics in complicated, multi-material environments at a modest computational expense.This presentation will describe the current concepts of the ReaxFF method, including parallel implementations and recently developed hybrid Monte Carlo and metadynamics concepts that significantly increases accessible time-scales. Also, we will present new development areas, including applications to ferroelectric materials, 2D-chalcogenides and extensions of ReaxFF with explicit electron terms (e-ReaxFF).
3:20 PM Invited
Recent Interatomic Potential Development Activities at Sandia: Xiaowang Zhou1; 1Sandia National Laboratories
Sandia is performing molecular-dynamics studies of two hydrogen-storage material problems: helium bubble growth in palladium tritides, and thermodynamics of Mg-B-H systems. To enable helium bubble growth simulations, the Pd-T-He interatomic potential must address two paradoxes: He is repulsive in He but attractive in Pd, and He has a small diffusion barrier but a large swelling in Pd. We have developed a Finnis-Sinclair type of Pd-T-He embedded-atom method potential to overcome both paradoxes. Preliminary molecular-dynamics simulations reveal not only He-bubble nucleation, but also fast He-cluster diffusion that was later verified by our density-function-theory calculations. Mg-B-H systems contain many molecules in amorphous forms, which cannot be modeled by conventional interatomic potentials. We have developed a molecular Mg-B-H force field where molecules are stabilized by intra-molecule potentials and interaction energy between molecules is correctly captured by pairwise inter-molecule potentials. This approach has been implemented in LAMMPS and successful simulations have been demonstrated.
3:40 PM Break
4:10 PM Invited
Second Nearest-neighbor Modified Embedded-atom Method Potential: Development, Validation and Challenges: Byeong-Joo Lee1; 1Pohang University of Science & Technology
The second nearest-neighbor modified embedded-atom method (2NN MEAM) interatomic potential is an extended version of the MEAM originally developed by Baskes. Over the last two decades, 2NN MEAM has been applied to more than hundred binary and multicomponent metal and covalent bonding systems, including carbide, nitride and hydride systems. In recent years, the formalism has also been extended in a way that combines with a charge equilibration scheme originally proposed by Goddard, to account for ionic bonding systems. In the present talk, the parameter optimization strategies, transferability and challenges in 2NN MEAM potential developments will be outlined with examples. The probable differences between 2NN MEAM and MEAM formalisms for a binary system, which should be taken care of when combining potentials from both formalisms to describe a higher order system, will also be outlined.
4:40 PM Cancelled
Development of a Modified Embedded-atom Method Interatomic Potential for 2D Titanium Carbides (Tin+1Cn) MXenes: Ning Zhang1; Yu Hong2; Mohsen Asle Zaeem2; 1University of Alabama; 2Colorado School of Mines
2D MXenes show unique and promising properties, however the lack of reliable nanoscale computational models has hindered understanding the nanoscale mechanisms controlling their properties. In this work, for the first time, we develop a modified embedded-atom method (MEAM) interatomic potential for Tin+1CnTx (T is –OH, –O or –F) MXenes by fitting to some important experimental and density functional theory (DFT) data, such as lattice constant, monolayer thickness, cohesive energy and elastic constant. The MEAM potential is also validated by evaluating the stacking fault, surface and defect formation energies. Through molecular dynamics simulations, we demonstrate that atoms rearrangement is followed by dislocation propagation when stretching the Ti2C flake uniaxially. DFT calculations evident that the transformed new phase is a metastable phase, it will converge to the original phase after full relaxation. In contrast, Ti3C2 and Ti4C3 show more brittle fracture behavior.
5:00 PM
MEAM-BO: Extension of MEAM to Include Bond Order for Polymer: Sungkwang Mun1; Ric Carino1; Andrew Bowman1; Steven Gwaltney2; Sasan Nouranian3; Mark Horstemeyer4; Michael Baskes2; 1Center for Advanced Vehicular Systems (CAVS); 2Mississippi State University; 3University of Mississippi; 4Liberty University
In this study, we extended Modified Embedded Atom Method (MEAM) force field to include the bond order to describe unsaturation in hydrocarbon system for more reliable and accurate polymer simulations with their associated structure-property relationships, such as reactive multicomponent (organic/metal) systems, polymer-metal interfaces, and nanocomposites. New bond order parameters and updated original MEAM parameters for hydrocarbons give comparable or more accurate properties relative to experimental and first-principles data than the classical reactive force fields REBO and ReaxFF. Such quantities include bond lengths, bond angles, and atomization energies at 0 K, dimer molecule interactions, rotational barriers, and the pressure-volume-temperature relationships of dense systems of small molecules. The new formalism is called Modified Embedded Atom Method with Bond Order (MEAM-BO). MEAM-BO is compatible with the original MEAM being able to utilize the literature parameters. Finally, the code has been implemented in LAMMPS, widely used parallel molecular dynamics software.