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Calculating Activation Energies in Diffusion Processes Using a Monte Carlo Approach in a Grid Environment [chapter]

Mark Calleja, Martin T. Dove
2004 Lecture Notes in Computer Science  
A Monte Carlo based method due to Mishin [1] for obtaining activation energies for ionic transport processes has been implemented for empirical-potential models and used in conjunction with Condor and  ...  Results are shown for Na + migrating in quartz, and O 2− vacancy hopping in CaTiO3.  ...  We would like to thank Mark Hayes (CeSC) and Rik Tyer (CCLRC) for useful discussions and the NERC (UK) (grant: Environment from the molecular level) for funding this work.  ... 
doi:10.1007/978-3-540-25944-2_63 fatcat:dxorbmjcsbgrtc54modvhb6ak4

First-Principles-Based Monte Carlo Simulation of Ethylene Hydrogenation Kinetics on Pd

Eric W. Hansen, Matthew Neurock
2000 Journal of Catalysis  
Subsequently, this database was used to simulate ethylene hydrogenation kinetics via a multisite Monte Carlo algorithm that treats coverage-dependent activation energies through bond-order conservation  ...  A first-principles-based kinetic Monte Carlo algorithm was used to simulate catalytic kinetics of ethylene hydrogenation on the welldefined Pd(100) surface.  ...  Using this first-principles-based approach, a multisite kinetic Monte Carlo (Fig. 4) algorithm was used to simulate ethylene hydrogenation kinetics.  ... 
doi:10.1006/jcat.2000.3018 fatcat:hiebnrizl5hkpn3t6tihewsiz4

Quantifying lateral adsorbate interactions by kinetic Monte-Carlo simulations and density-functional theory: NO dissociation on Rh(100)

A. P. van Bavel, C. G. M. Hermse, M. J. P. Hopstaken, A. P. J. Jansen, J. J. Lukkien, P. A. J. Hilbers, J. W. Niemantsverdriet
2004 Physical Chemistry, Chemical Physics - PCCP  
Monte-Carlo simulations based on interactions obtained from DFT provide a description that is only qualitatively useful.  ...  Second, interactions estimated using DFT calculations were significantly higher than the ones estimated from fitting the experiments.  ...  Diffusion was not modelled with Arrhenius-type rates, as realistic values would result in diffusion dominating all processes by orders of magnitude with the consequence that Monte-Carlo simulations become  ... 
doi:10.1039/b314944g fatcat:2xkpfdsyhngbzbzrrv2r4hcuqq

Monte Carlo radiation hydrodynamics: methods, tests and application to Type Ia supernova ejecta

U. M. Noebauer, S. A. Sim, M. Kromer, F. K. Röpke, W. Hillebrandt
2012 Monthly notices of the Royal Astronomical Society  
During the last few years, there have been rapid developments in the use of Monte Carlo methods for numerical radiative transfer simulations.  ...  In this paper the numerical tools of this method are presented and their accuracy is verified in a series of test calculations.  ...  D I S C U S S I O N In this paper we presented a Monte Carlo approach to radiationhydrodynamical problems in astrophysical environments.  ... 
doi:10.1111/j.1365-2966.2012.21600.x fatcat:drv7jvtndzbhvhuf7kk2iqo3b4

Self-learning kinetic Monte Carlo method: Application to Cu(111)

Oleg Trushin, Altaf Karim, Abdelkader Kara, Talat S. Rahman
2005 Physical Review B  
We present a novel way of performing kinetic Monte Carlo simulations which does not require an a priori list of diffusion processes and their associated energetics and reaction rates.  ...  procedure, or retrieved from a database in which previously encountered processes are stored.  ...  Once the processes are classified and macroscopic rates are calculated, we proceed to perform one Monte Carlo step in which a randomly selected process is executed.  ... 
doi:10.1103/physrevb.72.115401 fatcat:ovxbmhxvjvh5vfa6yj7mluzlmq

Hybrid Navier-Stokes/Monte Carlo method for reacting flow calculations

1992 Journal of Spacecraft and Rockets  
Bird'®) were performed on a grid using 40 x 33 mesh cells, shown in Fig. 2 in comparison with the grid used in the hybrid code calculations (identical to the one shown in Fig. 1).  ...  DE JONG ET AL.: REACTING FLOW CALCULATIONS 313 NW ANNU AANA Fig. 2 Grids used in hybrid and DSMC calculations.  ... 
doi:10.2514/3.26353 fatcat:tj7zron6zzamro6m2rnp2atsdi

Probabilistic models for drug dissolution. Part 1. Review of Monte Carlo and stochastic cellular automata approaches

Ana Barat, Heather J. Ruskin, Martin Crane
2006 Simulation modelling practice and theory  
Throughout the last decades, Monte Carlo (MC) techniques have been used in simulating various complex systems.  ...  approach.  ...  As there is no prior knowledge about the porosity, a probabilistic process is used to calculate the porosity along the diffusion pathway.  ... 
doi:10.1016/j.simpat.2006.01.004 fatcat:zo4e7ia4ubcdzpbahps5zra4ei

First-principles study of competing mechanisms of nondilute Li diffusion in spinel LixTiS2

Jishnu Bhattacharya, Anton Van der Ven
2011 Physical Review B  
Kinetic Monte Carlo simulations predict diffusion mechanisms mediated by triple vacancies and divacancies, which 2 leads to a strong concentration dependence of the chemical diffusion coefficient.  ...  This makes spinel Li x TiS 2 a useful model system to explore diffusion mechanisms in threedimensional intercalation compounds with octahedral Li occupancy.  ...  Acknowledgement The authors acknowledge financial support from DOE BES: EFRC Northeastern Center for Chemical Energy Storage DESC0001294 and TERAGRID for computational resources.  ... 
doi:10.1103/physrevb.83.144302 fatcat:cxtspujeqvac3d5bnh7lylxsne

Predicting activation energies for vacancy-mediated diffusion in alloys using a transition-state cluster expansion [article]

Chenyang Li, Thomas Nilson, Liang Cao, Tim Mueller
2021 arXiv   pre-print
Kinetic Monte Carlo models parameterized by first principles calculations are widely used to simulate atomic diffusion.  ...  However, accurately predicting the activation energies for diffusion in substitutional alloys remains challenging due to the wide variety of local environments that may exist around the diffusing atom.  ...  The average activation energies for Pt and 21 Ni diffusion as a function of the nearest-neighbor environment are shown in Figure 6 .  ... 
arXiv:2009.12474v3 fatcat:3nbx6vx2znf5xpa3zkkol52cme

Diffusion and clustering of substitutional Mn in (Ga,Mn)As

Hannes Raebiger, Maria Ganchenkova, Juhani von Boehm
2006 Applied Physics Letters  
C is studied using Lattice Kinetic Monte Carlo simulations.  ...  The Ga vacancy mediated microstructure evolution of (Ga,Mn)As during growth and post-growth annealing is studied using a multi-scale approach.  ...  A. Ayuela, and Mr. T. Hynninen for many valuable discussions. The generous computing resources of the Center for Scientific Computing (CSC) are acknowledged.  ... 
doi:10.1063/1.2219337 fatcat:swn3hm33yjepfmt2in2qq2d2ii

Development of a hybrid model to quantify the single and double strand breaks following the iron 57 de-excitation

H. Oudira, D. Lotfi, A. Saifi
2017 Pressacademia  
method, treatment of chemical reactions in the considered environment by the diffusion equation.  ...  by step based on Monte Carlo codes  ...  Stochastic Model of Monte Carlo The Monte Carlo method of the type step by step is adapted perfectly to the study of the physical and physic-chemical evaluation phases of the energy deposited in the target  ... 
doi:10.17261/pressacademia.2017.583 fatcat:qknptyh4sjd2xlx6gu4n7eijvq

Quantum Monte Carlo with ground-state input to investigate methane reactions on supported metal film catalysts [article]

Philip E. Hoggan
2022 arXiv   pre-print
This work shows how to use Quantum Monte Carlo calculations to take (user-guided) information summarising chemistry of heterogeneous catalysis from a generic Jastrow factor, that allows electron correlation  ...  This, in turn, gives accurate values of properties, in particular the activation barrier for stretching one methane C-H bond, before adsorbing CH3- and H- on vicinal nickel atoms in the close-packed (111  ...  Acknowledgements The authors wish to thank the President A Mahul and staff of the Regional Computation facility (CRRI) on Clermont University Campus, for generous allocations of computer resources.  ... 
arXiv:2105.10973v2 fatcat:x5it2fvnovatfp5w64elt3tndy

Modeling the Microstructural Evolution During Constrained Sintering

Rasmus Bjørk, Hendrik Lund Frandsen, Nini Pryds, E. Olevsky
2015 Journal of The American Ceramic Society  
The model couples an existing kinetic Monte Carlo (kMC) model for free sintering with a finite element model (FEM) for calculating stresses on a microstructural level.  ...  The constrained sintering results in a larger number of pores near the substrate, as well as anisotropic sintering shrinkage, with significantly enhanced strain in the central upper part of the sample  ...  Veena Tikare who developed the used kMC model, as well as Dr. Michael Braginsky, whose unpublished work inspired some of the approaches presented here.  ... 
doi:10.1111/jace.13701 fatcat:ghcbfo424vae7bh4piuz6cg3pe

Cs diffusion in SiC high-energy grain boundaries

Hyunseok Ko, Izabela Szlufarska, Dane Morgan
2017 Journal of Applied Physics  
In this work, Cs diffusion through high energy grain boundaries (HEGBs) of cubic-SiC is studied using an ab-initio based kinetic Monte Carlo (kMC) model.  ...  The HEGB environment was modeled as an amorphous SiC (a-SiC), and Cs defect energies were calculated using density functional theory (DFT).  ...  Therefore, in this work, we use an approach based on kinetic Monte Carlo (kMC).  ... 
doi:10.1063/1.4989389 fatcat:o42tsurpircrjavap2nkvults4

Ag diffusion in SiC high-energy grain boundaries: Kinetic Monte Carlo study with first-principle calculations

Hyunseok Ko, Jie Deng, Izabela Szlufarska, Dane Morgan
2016 Computational materials science  
The diffusion of silver (Ag) impurities in high energy grain boundaries (HEGBs) of cubic (3C) silicon carbide (SiC) is studied using an ab initio based kinetic Monte Carlo (kMC) model.  ...  At 1200-1600C, Ag in a HEGB is predicted to exhibit an Arrhenius type diffusion and with a diffusion prefactor and effective activation energy of (2.73+-1.09)*10-10 m2s-1 and 2.79+-0.18 eV, respectively  ...  Computations in this work benefitted from the use of the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number OCI-1053575.  ... 
doi:10.1016/j.commatsci.2016.04.027 fatcat:mvdtx5mlrbfozgpcmtczsqbtai
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