Fig. 2
Left: A snapshot of a molecular dynamics simulation of Fe0.9O0.1 with 57,600 Fe (pink) and 6400 O (blue) atoms, at performed \(P \approx 330\) GPa and \(T = 5300\) K. Red lines indicate a \(4\times 4\times 4\) fractioning of the simulation box in sub-volumes, each including 900 Fe and 100 O atoms. Right: Probability distributions for Fe systems with average compositions of 10, 20 and 30 mol.% O (blue, green and orange points, respectively). The probability is that of observing a simulation sub-volume (1/64 of the total volume) with n oxygen atoms, given a sub-volume contains 1000 atoms and 100 of these are O atoms on average for the 10 mol.% O case. A normal distribution is fit to underestimate the most rare low O concentration observations for the 10 % case (dotted line) and to underestimate the highest concentration observations in the 20 and 30 % cases (dashed lines).
