THE DIELECTRIC RESPONSE OF WATER IN HIGH ELECTRIC-FIELDS - EQUILIBRIUM WATER THICKNESS AND THE FIELD DISTRIBUTION

Adsorption and reaction of water at metal surfaces can be strongly inf luenced by high surface electric fields. A numerical model, which incl udes a field-dependent relative permittivity of water, has been develo ped to predict the equilibrium thickness of the condensed water layer and its effect on the field distribution around a field emitter tip. T hin water layers weaken the field at the tip surface while thick layer s concentrate it. When the water becomes sufficiently thick, the field at the tip surface becomes greater than the field at a clean tip surf ace for the same applied potential. (C) 1998 Published by Elsevier Sci ence B.V. All rights reserved.