  Stable non-crystalline toluene films of micrometer and nanometer thicknesses
were grown by vapor deposition at distinct rates and probed by Fast Scanning
Calorimetry. Fast scanning calorimetry is shown to be extremely sensitive to
the structure of the vapor-deposited phase and was used to characterize
simultaneously its kinetic stability and its thermodynamic properties.
According to our analysis, transformation of vapor -deposited samples of
toluene during heating with rates in excess 10^5 K/s follows the zero-order
kinetics. The transformation rate correlates strongly with the initial enthalpy
of the sample, which increases with the deposition rate according to sub-linear
law. Analysis of the transformation kinetics of vapor deposited toluene films
of various thicknesses reveal a sudden increase in the transformation rate for
films thinner than 250 nm. The change in kinetics correlates with the surface
roughness scale of the substrate, which is interpreted as evidence for kinetic
anisotropy of the samples. The implications of these findings for the formation
mechanism and structure of vapor deposited stable glasses are discussed.
