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 1.21

Use Slater’s rules to calculate the effective nuclear charge Z* for the elements Li through F. How is the trend in Z* reflected in the ionization energies in this group?
 
 

Answer:
 
Element
Electron Configuration
Z* (Calculated)
Ionization Energy (eV)
Li
(1s2)(2s1)
3 - [2(0.85)] = 1.30
5.392
Be
(1s2)(2s2)
4 - [2(0.85) + 1(0.35)] = 1.95
9.322
B
(1s2)(2s22p1)
5 - [(2(0.85) + 2(0.35)] = 2.60
8.298
C
(1s2)(2s22p2)
6 – [2(0.85) + 3(0.35)] = 3.25
11.260
N
(1s2)(2s22p3)
7 – [2(0.85) + 4(0.35)] = 3.90
14.534
O
(1s2)(2s22p4)
8 – [2(0.85) + 5(0.35)] = 4.55
13.618
F
(1s2)(2s22p5)
9 – [2(0.85) + 6(0.35)] = 5.20
17.422

Z* and IE generally parallel each other since both increase with atomic number, but Z* does not account for the anomalies found for Be/B and N/O.