A MOLECULAR-DYNAMICS SIMULATION OF ELECTRIFIED PLATINUM WATER INTERFACES

A Molecular Dynamics simulation of water between charged platinum walls has been carried out. A homogeneous external electric field of 10(10) V/m was applied. The immediate consequence of the applied field is a reorientation of the water dipoles. Close to the platinum surface, however, the field is superimposed on the specific water/platinum interactions, and therefore the average orientation of the water molecules is different from that of the bulk water. The water mobility is very small on the surfaces and it increases perpendicular to it in the interphases while it decreases in the bulk due to the electrification. There are peak-shifts in the power spectra of the translational, rotational and vibrational modes of the interfacial water. The electrostatic potential profile shows strong non-linearities in the interphases while there is an almost linear potential drop in the middle of the lamina.