• Citation: S. Zhou, C. Jiang, E. Xiao, S. Bandi, M.W.D. Cooper, M. Jin, D. H Hurley, M. Khafizov, and C.A. Marianetti (2025), "Parameterizing empirical interatomic potentials for predicting thermophysical properties via an irreducible derivative approach: the case of ThO2 and UO2", Journal of Physics: Condensed Matter, 37(25), 255901. DOI: 10.1088/1361-648x/ade10a.
    Abstract: The accuracy of classical physical property predictions using molecular dynamics simulations is determined by the quality of the interatomic potentials. Here we introduce a training approach for empirical interatomic potentials (EIPs) which is well suited for capturing phonons and phonon-related properties. Our approach is based on direct comparisons of the second- and third-order irreducible derivatives (IDs) between an EIP and the Born-Oppenheimer potential within density functional theory (DFT) calculations. IDs fully exploit space group symmetry and allow for training without redundant information. We demonstrate the fidelity of our approach in the context of ThO2 and UO2, where we optimize parameters of an embedded-atom method potential in addition to core-shell interactions. Our EIPs provide thermophysical properties in good agreement with DFT and outperform widely utilized EIPs for phonon dispersion and thermal conductivity predictions. Reasonable estimates of thermal expansion and formation energies of Frenkel pairs are also obtained.

    Notes: This potential was designed for phonon and phonon thermal transport simulation of ThO2 and UO2, using an EAM model combined with a core-shell model.

  • GULP (2025--Zhou-S--U-Th-O--GULP--ipr1)
    Notes: This file was provided by Shuxiang Zhou on June 18, 2025.
    File(s):
  • LAMMPS pair_style eam/alloy, bond_style harmonic (2025--Zhou-S--U-Th-O--LAMMPS--ipr1)
    See Computed Properties
    Notes: This file and the additional parameters were provided by Shuxiang Zhou on June 18, 2025. Note that with LAMMPS the core/shell model requires data files that define separate charges for the core and shell, and core-shell bonds for each atom. See the associated documentation link for more details.
    File(s): Link(s):
    LAMMPS documentation on core/shell model https://docs.lammps.org/Howto_coreshell.html
    Parameters:
    U_core_charge -7.289967810275657
    U_shell_charge 10.244531498647017
    Th_core_charge -9.72676181359563
    Th_shell_charge 12.681325501966988
    O_core_charge 1.7687904690362286
    O_shell_charge -3.2460723132219083

    bond_style harmonic
    bond_coeff U_core_shell 551.982131308207 0.0
    bond_coeff Th_core_shell 1204.9865326130625 0.0
    bond_coeff O_core_shell 436.85862591019253 0.0

Date Created: October 5, 2010 | Last updated: July 17, 2025