This example illustrates the measurement of the ionization potential (Ip) of bathophenanthroline (organic light-emitting diode material). The measurement was made with an AC-3. The horizontal axis in the figure is incident UV energy. The vertical axis is the square root of the electron emission count. The ionization potential (Ip) was estimated to be 6.48 eV based on photoemission threshold energy.

Fig.1 Ionization potential measurement of Bathophenanthroline