The Surface Tension of Liquid Silicon and Germanium

Abstract
The surface tensions of liquid silicon and germanium were determined using the drop weight method. 600 dynes/cm was found for germanium and 720 dynes/cm for silicon at their freezing points and argon atmosphere. The parachors of the group IVb elements as derived from surface tension measurements of the molten elements are compared with the atomic parachors calculated from compounds. The differences are interpreted as structural parachors which indicate that the bonding between neighboring atoms in the liquid state increases in nearly uniform steps from lead to tin and to germanium. No further increase of the structural parachor takes place in silicon which is consistent with the fact that only four electrons per atom are available for bonding.