  We study crystal nucleation of the Weeks-Chandler-Andersen (WCA) model, using
the recently introduced Persistent Embryo Method (PEM). The method provides
detailed characterization of pre-critical, critical and post-critical nuclei,
as well as nucleation rates that compare favorably with those obtained using
other methods (umbrella sampling, forward flux sampling or seeding). We further
map our results to a hard sphere model allowing to compare with other existing
predictions. Implications for experiments are also discussed.
