  The energy per particle of many body wavefunctions that mix Laughlin liquid
with crystalline correlations for periodic samples in the Haldane-Rezayi
configuration is numerically evaluated for periodic samples. The Monte Carlo
algorithm is employed and the wave functions are constructed in such a way that
have the same zeroes as the periodic Laughlin states. Results with up to 16
particles show that these trial wavefunctions have lower energy than the
periodic Laughlin states for finite samples even at $\nu=1/3$. Preliminary
results for 36 particles suggest that this tendency could reach the
thermodynamic limit. These results get relevance in view of the very recent
experimental measures that indicate the presence of periodic structures in the
2DEG for extremely small temperatures and clean samples, inclusive at main FQHE
filling fractions $\nu=1/3,2/3 $.
