Abstract
The amorphous phase state of suspended nanoparticles affects their atmospheric lifetimes and environmental impact. Influence of relative humidity and chemical composition on the glass-to-liquid transition is well-known. However, the influence of the particle size on the phase transition remains uncertain. Here we show experimental data that probe the amorphous phase transition of suspended sucrose particles as a function of particle size. The depression in glass-transition temperature follows the Gibbs-Thomson or Keesom-Laplace predicted proportionality of ΔT(g) ∝ D(-1) for particles 100-700 nm in diameter, but the proportionality changes to ΔT(g) ∝ D(-1/2) for smaller sizes. Literature data for glass-transition temperature depression in thin films and nanoconfined compounds show similar and strong deviations from the expected D(-1) behavior. While the observed proportionalities remain incompletely understood, the results here provide evidence that the deviation from ΔT(g) ∝ D(-1) is not attributable to substrate effects.