Spreading Index of Molten Alkali Halides on the Charged Surface of Liquid Bismuth

This work presents and analyzes experimental results on the measurement of interfacial tension between liquid bismuth and melts of sodium chloride, bromide, or iodide over a wide range of applied voltages. In the anodic polarization region, a critical potential was found above which the two-phase system loses mechanical stability. It is shown that the observed phenomenon is associated with the transition of the system to a film-wetting regime on the surface. The magnitude of the critical wetting potential decreases with increasing polarizability of the anion in the salt phase. Near the critical potential, a quadratic dependence of the wetting index on the applied voltage is observed.