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BELL SYSTEM TECHNICAL JOURNAL 



atoms have filled up Zd bands, losing their more loosely bound 4^ 

 electrons when there are available places of lower energy. The data 

 for palladium indicate that this element has the same number of outer 



NUMBER OF QUANTUM STATES PER UNIT ENERGY 



Fig. 12 — Energy levels in the 3d and As shells in copper, according to Slater. 

 Similar levels are believed to exist in nickel and cobalt with the levels filled to "10" 

 and "9" respectively. 



electrons as nickel ; this might be expected since palladium lies directly 

 below nickel in the periodic table. When the similar but heavier 

 platinum is added to nickel, the decrease in average atomic moment 



