Energy Levels of Charged Particles in Condensed Phases

The outer potential,, can be measured physically as a difference of electrostatic potential between two points in the same gas or vacuum phase. On the other hand, the surface potential, x, which is a difference of electrostatic potential between two different phases, cannot be measured so that the inner potential, also cannot be measured in a straightforward way. 

6 Enetsy Levels of Charged Particles in Condensed Phases 

In electrochemistry, we deal with the energy level of charged particles such as electrons and ions in condensed phases. The electrochemical potential, Pi,of a charged particle i in a condensed phase is defined by the differential work done for the charged particle to transfer from the standard reference level (e.g. the standard gaseous state) at infinity = 0) to the interior of the condensed phase. The electrochemical potential may be conventionally divided into two terms the chemical potential Pi and the electrostatic energy Zi e as shown in Eqn. 1-21  

In this textbook, we use the real potential cti rather than the electrochemical potential Pi to represent the energy level of charged particles in condensed phases. 

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