  The nuclear liquid-gas phase transition of the system in ideal thermal
equilibrium is studied with antisymmetrized molecular dynamics. The time
evolution of a many-nucleon system confined in a container is solved for a long
time to get a microcanonical ensemble of a given energy and volume. The
temperature and the pressure are extracted from this ensemble and the caloric
curves are constructed. The present work is the first time that a microscopic
dynamical model which describes nuclear multifragmentation reactions well is
directly applied to get the nuclear caloric curve. The obtained constant
pressure caloric curves clearly show the characteristic feature of the
liquid-gas phase transition, namely negative heat capacity (backbending), which
is expected for the phase transition in finite systems.
