Periodic table ionization potential variation

The Ion source Is a radio frequency vacuum discharge source and Is Illustrated In Figure 3. The Ionization efficiency of this source is uniform within a factor of three, due to the fact that the Ionizing energy available Is so much greater than the Ionization potential of any element. This Is one of the most attractive features of the technique, since It allows us to analyze every element on the periodic table without large variations In sensitivity. 

Variation of Ionization Potential in a Family. Going down a column in the periodic table, one finds a steady decrease in ionization potential (Fig. 3.6). The decreases from element to... 

---