Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 43 for “"Interatomic Potential"”.
-
Spin-Aware Neural Network Interatomic Potential for Atomistic Simulation
… but at high cost and limited scale. Empirical potentials are faster and scale better, but cannot compare to ab initio in numerical and physical accuracy. Machine learning (ML) interatomic potentials (IPs) of recent years offer a balance: excellent phenomenology and accuracy, while scaling well …
-
Developing a new interatomic potential and atomistic study of NiTiHf
… alloys, NiTiHf has shown to have great potential, by having high transformation temperatures, lower preparation cost and good thermal stability. However, until today, most studies conducted on NiTiHf have focused on a limited range of compositions due to the difficulties and high cost of …
-
The round state interatomic potential between pairs of closed-shell atoms.
Dept. of Physics. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1973 .P44. Source: Masters Abstracts International, Volume: 40-07, page: . Thesis (M.Sc.)--University of Windsor (Canada), 1973.
-
Mechanics of Boron Nitride Nanotubes: A Continuum Theory Based on the Interatomic Potential
A hybrid atomistic/continuum model based on the interatomic potential for boron nitride is also developed to study the Stone-Wales transformation (90° rotation of an atomic bond) in boron nitride nanotubes under tension. It is found that the critical strains for Stone-Wales transformation for …
-
Enabling the simulation of helium transport in lithium for fusion devices
Nuclear fusion is a potential source of abundant, carbon-free energy. However, creating a nuclear fusion device with the ability to efficiently produce energy is a challenge to modern engineering. The tokamak is a device that has been designed to produce power through nuclear fusion. Finding the …
-
On the formulation and the calculation of the harmonic contributions to the Debye-Waller factor in metals (sodium)
… for cubic metals with small ion cores where the interatomic potential extends to many neighbours. This has been achieved in terms of various wave-vector dependent tensors, following the work of Shukla and Taylor (1974) on the cubic anharmonic Helmholtz free energy. The contribution to the various …
-
Simulation of Bulk and Grain Boundary Diffusion in B2 NiAl
… were performed using an embedded atom interatomic potential developed to fit NiAl properties. Diffusion in the bulk occurs through a variety of cyclic mechanisms that accomplish the motion of the vacancy through nearest neighbor jumps restoring order to the alloy at the end of the …
-
Nanomechanics model for static equilibrium
… behavior of materials under static loads. Interatomic potential energy was used to maintain equilibrium among atoms under static loads and constraints. In addition, the atomistic model was coupled with the finite element analysis model so that more flexible loads and constraints could be …
-
A computational study of germanium dioxide
… on germanium dioxide. These have been done with interatomic pair potentials developed with the aid of a fitting procedure. Results for the crystalline modifications and the glassy state are presented. This includes static and dynamic properties of the GeO$_{2}$ modifications. Germanium dioxide is …
-
Molecular dynamics analysis of spectral characteristics of phonon heat conduction in silicon
… are modeled with the environment dependent interatomic potential (EDIP), which was designed to represent the bulk phases of silicon. Temperature and phonon frequency dependent relaxation times are extracted from the MD simulations and used to generate a detailed picture of phonon transport. …
-
Nanoscale solidification of metals by atomistic simulations: From nucleation to nanostructural evolution
… modified embedded atom method (2NN-MEAM) potentials. Spontaneous homogenous nucleation from the melt was produced without any influence of pressure, free surface effects and impurities. We also study the effect on the simulation size on homogenous nucleation and the heterogeneity in …
-
Improving radiation resistance of solid solutions by addition of defect trapping solutes: Atomistic simulations and continuum modeling
… calculation of the system energetics based on an interatomic potential. This greatly facilitates predictions for transport behavior and allows for the characterization of clusters too complex to parameterize manually. It is used here to examine vacancy and solute flux behavior in a Cu-Ag and a …
-
First and Second-Principles Atomistic Modelling of Ge-Sb-Te Phase-Change Memory Materials
… losing the accuracy of the quantum-mechanical potential-energy surface. This thesis presents the de- velopment, validation and applications of a machine-learned interatomic potential, trained on data obtained from density-functional theory calcu- lations of Ge−Sb−Te materials, which are widely …
-
Data-driven linear interatomic potentials
… due to the rapid development of data-driven interatomic potential frameworks over the last decade. This thesis presents two novel frameworks, namely 'atomic permutation invariant polynomials' and 'atomic cluster expansion'. Both frameworks are linear models that can be used to create …
-
Measuring atomic properties with an atom interferometer
… measurements offer detailed insight into the interatomic potential between sodium atoms and the gases. Theoretical predictions of the interatomic potentials are challenged by these results, which should encourage a renewed effort to better understand these potentials. The second experiment …
-
Helium behavior at fcc-bcc semicoherent interfaces: trapping, clustering, nucleation, and growth of cavities
… a model fcc-bcc interface, a predictive Cu-Nb-He interatomic potential is constructed using density functional theory. These calculations show that two-body radial forces are sucient to describe interactions of He with fcc Cu and bcc Nb. Atomistic simulations reveal that He is initially trapped in …
-
Electronic effects in radiation damage simulations in metals
… is con�fined to describing bonding via the interatomic potential. This is generally sufficient for low radiation energies. However high energy atoms lose a signi�ficant proportion of their energy to electronic excitations, therefore a simulation of the relaxation of a metallic lattice after …
-
A scalable machine learning approach to thermal and non-thermal order-disorder phase transitions with ab initio accuracy
… based on high-fidelity machine learning interatomic potentials. These tools are utilized to investigate three distinct out-of- equilibrium regimes: • Ultrafast non-thermal melting in silicon: a novel framework based on constrained density functional perturbation theory and machine …
-
The phase transition of the rubidium halides
… that the relatively simple Born model for the interatomic potential energy is sufficient to successfully predict the cohesive energies, the transition pressure, the effects of non-hydrostatic stress, energy differences, and the volume changes at the transition in the Rubidium Halides. Although …
-
X-ray diffraction study of the high-density phases of solid 4He
… density dependence of the an harmonicity of the interatomic potential within accessible experimental conditions. One can then study the decreasing quantum nature of the solid. The research presented in this thesis involves x-ray diffraction studies of the high density phases of 4He to 60 …
Page 1 of 3