Fig. 5: Phase diagram determined by a semi-grand canonical (sGC) and fixed-composition ensemble nested sampling (NS).
From: Machine-learned interatomic potentials for alloys and alloy phase diagrams
Solid lines show sGC NS composition as a function of temperature for each Δμ = μAg − μPd, with approximately horizontal jogs indicating finite-size broadened discontinuities associated with the liquidus–solidus (L–S) gap. Dotted lines indicate experimentally observed L–S gap. Circles indicate constant composition NS specific heat maxima corresponding to liquid–solid and solid–solid phase transition temperatures. We have shifted all simulation results in this figure up by 200 K to make it easier to compare the width of the L–S gap with the experiment. The experimental liquidus and solidus are adapted from several sources, refs. 66,67,68. The slight difference between the NS results and coexistence results can be explained by the system size: 64 atoms for NS and 16,384 atoms for coexistence. Error bars for fixed-composition NS are the full-width half-maximum obtained from the heat capacity peaks.
