  We consider nonlinear Schrodinger equations with either local or nonlocal
nonlinearities. In addition, we include periodic potentials as used, for
example, in matter wave experiments in optical lattices. By considering the
corresponding semiclassical scaling regime, we construct asymptotic solutions,
which are concentrated both in space and in frequency around the effective
semiclassical phase-space flow induced by Bloch's spectral problem. The
dynamics of these generalized coherent states is governed by a nonlinear
Schrodinger model with effective mass. In the case of nonlocal nonlinearities
we establish a novel averaging type result in the critical case.
