We present the pressure area isotherms for Langmuir films made of cali
x[8]arene, the calix[8]arene/C-60 complex, and the calix[8]arene/C-70
complex, all of them measured at 306.1 K. A Brewster angle microscope
was used to observe the phases shown by the pi-A isotherms. In these t
hree cases, we found a solid phase and its solid-gas coexistence but n
o expanded liquid phases. The Langmuir films made of calix[8]arene and
the calix[8]arene/C-60 complex are very similar. The experimental inf
ormation is consistent with the assumption that C-60 is situated insid
e the cavity of calix[8]arene. The Langmuir films of calix[8]arene and
the calix[8]arene/C-70 complex are not very similar; we present a dis
cussion to explain the origin of this difference.