Derivation of enhanced potentials for plutonium dioxide and the calculation of lattice and intrinsic defect properties

A new potential has been derived for plutonium dioxide and used to calculate its lattice and defect properties. The Pu ⁴⁺ ⋯ O ²⁻ potential is obtained via a combination of empirical fitting to crystal structural data and parametric fitting to additional physical properties, while the O ²⁻ ⋯ O ²⁻ potential is transferred from an earlier publication on UO ₂ . The overall potential is subsequently verified and validated by calculation of elastic and dielectric constants, whose values agree favourably with those measured experimentally. Calculations are then presented of the intrinsic defect formation energies and predictions of the expected type of intrinsic disorder made.