I am studying molecular junctions. I have found IV behavior that shows a Voffset of -1V in a Log I - V curve that resembles a diode. I posted an image of the IV data. The second plot shows the feature I am speaking of clearly. Are there any examples of this offset in the literature. The measurements are two-point probe DC measurements taken in the dark. There is no gate electrode present.

 

I'm not sure what kind of junction you are talking about, and I have even fewer ideas about the conditions of measurement. What is it that you find so unusual about plot #2?