  In this work, we consider a diffusive two-species d-dimensional model and
study it in great details. Two types of particles, with hard-core, diffuse
symmetrically and cross each other. For arbitrary dimensions, we obtain the
exact density, the instantaneous, as well as non-instantaneous, two-point
correlation functions for various initial conditions.
  We study the impact of correlations in the initial state on the dynamics.
  Finally, we map the one-dimensional version of the model under consideration
onto a growth model of RSOS type with three states and solve its dynamics.
