  We show results from simulations of the Langevin dynamics of a
two-dimensional scalar model with competing interactions for ultrathin magnetic
films. We find a phase transition from a high temperature disordered phase to a
low temperature phase with both positional and orientational orders. Both kinds
of order emerge at the same temperature, probably due to the isotropy of the
model Hamiltonian. In the low temperature phase orientational correlations show
long range order while positional correlations show only quasi-long-range order
in a wide temperature range. The orientational correlation length and the
associated susceptibility seem to diverge with power laws at the transition.
While at zero temperature the system exhibits stripe long range order, as
temperature grows we observe the proliferation of different kinds of
topological defects that ultimately drive the system to the disordered phase.
The magnetic structures observed are similar to experimental results on
ultrathin ferromagnetic films.
