  Our series of articles is devoted to high-precision molecular dynamics
simulation of mixed actinide-oxide (MOX) fuel in the approximation of rigid
ions and pair interactions (RIPI) using high-performance graphics processors
(GPU). In this first article 10 most recent and widely used interatomic sets of
pair potentials (SPP) are assessed by reproduction of solid phase properties of
uranium dioxide (UO2) - temperature dependences of the lattice constant, bulk
modulus, enthalpy and heat capacity. Measurements were performed with 1K
accuracy in a wide temperature range from 300K up to melting points. The best
results are demonstrated by two recent SPPs MOX-07 and Yakub-09, which both had
been fitted to the recommended thermal expansion in the range of temperatures
300-3100K. They reproduce the experimental data better than the widely used
SPPs Basak-03 and Morelon-03 at temperatures above 2500K.
