  We investigated the homogenous nucleation of the stoichiometric B2 and B33
phases in the Ni50Zr50 alloy using the persistent embryo method and the
classical nucleation theory. The two phases become very close competitors at
large supercoolings, which is consistent with the experimental observations. In
the case of the B2 phase, the linear temperature dependence of the solid-liquid
interface (SLI) free energy extrapolated to the melting temperature leads to
the same value as the one obtained from the capillarity fluctuation method
(CFM). In the case of the B33 phases, the SLI free energy is also a linear
function of temperature at large supercoolings but the extrapolation to the
melting temperature leads to a value which is considerably different from the
CFM value. This is consistent with the large anisotropy of the SLI properties
of the B33 phase nearby the melting temperature observed in the simulation of
the nominally flat interface migration.
