  We investigate vapor homogeneous nucleation in a superheated Lennard Jones
liquid with computer simulations. Special simulation techniques are required to
address this study since the nucleation of a critical vapor bubble --one that
has equal chance to grow or shrink-- in a moderately superheated liquid is a
rare event. We use the Seeding method, that combines Classical Nucleation
Theory with computer simulations of a liquid containing a vapor bubble to
provide bubble nucleation rates in a wide temperature range. Seeding has been
successfully applied to investigate the nucleation of crystals in supercooled
fluids and here we apply it for the fist time --to the best of our knowledge--
to the liquid-to-vapor transition. We find that Seeding provides nucleation
rates that are consistent with independent calculations not based on the
assumptions of Classical Nucleation Theory. Different criteria to determine the
radius of the critical bubble give different rate values. The accuracy of each
criterion depends of the degree of superheating. Moreover, Seeding simulations
show that the surface tension depends on pressure for a given temperature.
Therefore, using Classical Nucleation Theory with the coexistence surface
tension does not provide good estimates of the nucleation rate.
