Scanning tunneling microscopy and ''molecule corrals'' were used to me
asure the temperature dependence of the rate of molecular ordering in
monolayer liquid crystal films. Molecule corrals are circular etch pit
s, 3.35 Angstrom deep on the basal surface of graphite formed by high-
temperature oxidation. A strong negative relationship between temperat
ure and nucleation rate was observed, consistent with a nucleation gro
wth mechanism of molecular self-assembly. From a fit of classical nucl
eation theory the melting temperature of the film was found to be T-me
lt = 318 +/- 6 K, the thermodynamic driving force for nucleation Delta
F-n(T-melt - T)/T-melt = 1.1 +/- 0.3 kcal mol(-1), and the preexepone
ntial factor A = (1.8 +/- 0.8) x 10(8) Angstrom(-2) s(-1).