The third order susceptibilities chi((3)) of Langmuir Blodgett films o
f two series of octasubstituted metallophthalocyanines 1 and 2 have be
en measured by Third Harmonic Generation (THG) experiments at 1.064 an
d 1.904 mu m. The results indicate that the hydrogen bonding has a ver
y weak influence in their nonlinear response. Preliminary studies in s
olution of tetrasubstituted metallophthalocyanines have been also perf
ormed.