Liquid-to-crystal nucleation has been studied extensively through droplet
experiments to locate examples of homogeneous nucleation. However, prior to
this work very few examples have been found, which implies that the
experiments have not been able to isolate heterogeneous nucleants in a small
percentage of the droplets as is required. In this research,
electrohydrodynamic atomization (EHD) is used to produce sub-Micron droplets
of pure elements that are largely free of heterogeneous nucleants.
Diffraction patterns of individual EHD-produced droplets are viewed to
determine the fraction of crystalline droplets produced as a function of
droplet radius. These results are compared to theories for surface and
volume heterogeneous nucleation and for homophase nucleation. It is found
that Si and Ge nucleate through either homogeneous nucleation or nucleation
by homophase impurities. Nucleation results for vanadium and iron were not
conclusive.