Enter the effective nuclear charge and the atom number of the atom into the calculator to determine the screening constant.

Screening Constant Formula

The following equation is used to calculate the Screening Constant.

SC = Z - Zeff
  • Where Sc is the screening constant
  • Z is the atomic number of the atom
  • Zeff is the effective nuclear charge

To calculate the screening constant, subtract the effective nuclear charge from the atomic number of the atom.

What is a Screening Constant?


A screening constant is a measure of the shielding of an electron from the charge of the nucleus and other inner electrons.

How to Calculate Screening Constant?

Example Problem:

The following example outlines the steps and information needed to calculate Screening Constant.

First, determine the atomic number of the atom. In this case, the atomic number is 50.

Next, determine the effective nuclear charge. This is calculated to be 40 .

Finally, calculate the screening constant using the formula above:

SC = Z – Zeff

SC = 50 – 40

SC = 10 shielding