B. E. Douglas, D. H. McDaniel, J. J. Alexander, Concepts and Models of Inorganic Chemistry, 3rd edition, John Wiley & Sons, New York, 1994, page 52.

Problem 1.13

Write the electron configuration past the noble gas core (for example, F, [He]2s22p5) for Rb, La, Cr, Fe, Cu, Tl, Po, Gd, and Lu.
 
 
 
 

Answer:

Rb [Kr]5s1

La [Xe]6s25d1

Cr [Ar]4s13d5

Fe [Ar]4s23d6

Cu [Ar]4s13d10

Tl [Xe]4f145d106s26p1

Po [[Xe]4f145d106s26p4

Gd [Xe]6s25d14f7

Lu [Xe]6s25d14f14