Calculating S (shielding constan)

Sum together the contributions as described in the appropriate rule above to obtain an estimate of the shielding constant, S , which is found by totaling the screening by all electrons except the one in question.

where

• ni is the shielding of the electrons subject to Slater's rules
• Si is the shielding of the electrons subject to Slater's rules

• Example 1 : The Shielding of 3p Electrons of Nitrogen Atoms What is the shielding constant experienced by a 2p electron in the nitrogen atom?

  Given: Nitrogen (N)

  Asked for: S , the shielding constant, for a 2p electron

  Strategy:

• Determine the electron configuration of nitrogen, then write it in the appropriate form.
• Use the appropriate Slater Rule to calculate the shielding constant for the electron.

• Solution A N: 1s² 2s² 2p³

  N: (1s²)(2s²,2p³)

  Solution B

• the 1s electrons shield the other 2p electron to 0.85 "charges".
• the 2s and 2p electrons shield the other 2p electron equally at 0.35 "charges".