  Generalization of Gaussian trial wave functions in quantum molecular dynamics
models is introduced, which allows for long-range correlations characteristic
for composite nuclear fragments. We demonstrate a significant improvement in
the description of light fragments with correlations. Utilizing either type of
Gaussian wave functions, with or without correlations, however, we find that we
cannot describe fragment formation in a dynamic situation. Composite fragments
are only produced in simulations if they are present as clusters in the
substructure of original nuclei. The difficulty is traced to the delocalization
of wave functions during emission. Composite fragments are produced abundantly
in the Gaussian molecular dynamics in the limit $\hbar \rightarrow 0$.
