Work, maximum constancy

The energy required to extract an electron from the organic solid to a point in vacuum outside its surface, i.e., the work function

maximum kinetic energy as function of the photon energy. The remarkable constancy of the work function, which is independent of the photon energy, leads to the following conclusions (1) the probability of the electron abstraction from the solid does not vary with the photon energy ... 

These authors suggest that the decrease in work function with further uptake of CO after going through a maximum is due to physisorbed CO on top of a chemisorbed virgin layer. For the surface at 100°K the constancy of the work function beyond the point where it has increased to... 

Which means that under isochrone-adiabatic conditions maximum useful work is equal to change of the internal energy U. Because of this the internal energy is also called isochrone-adiabatic potential. It is, however, very difficult to provide for the constancy of volume and even more so entropy of the system. 

Enthalpy is the isobar-adiabatic potential, i.e., measure of maximum useful work at constant pressure and entropy. However, it is difficult to maintain and control constancy of entropy under real conditions. 

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