Enter the electronegativity of atom A and atom B into the calculator to determine the percentage ionic character.

Ionic Character Percentage Formula

The following formula is used to calculate the percentage ionic character in a bond. 

IC = (1 - e^{(-0.25 * (Xa - Xb)^2)}) * 100

Variables:

  • IC% is the percentage ionic character (%)
  • Xa is the electronegativity of atom A
  • Xb is the electronegativity of atom B
  • e is the base of the natural logarithm (approximately equal to 2.71828)

To calculate the percentage ionic character, subtract the electronegativity of atom B from the electronegativity of atom A. Square the result and multiply by -0.25. Use the base of the natural logarithm to raise e to the power of this result. Subtract this value from 1 and multiply by 100 to get the percentage ionic character.

What is an Ionic Character Percentage?

Ionic Character Percentage is a measure of the degree of ionicity of a chemical bond. It is calculated based on the difference in electronegativity between the two atoms involved in the bond. The higher the difference in electronegativity, the higher the ionic character percentage, indicating a more ionic bond. Conversely, a lower difference in electronegativity results in a lower ionic character percentage, indicating a more covalent bond.

How to Calculate Ionic Character Percentage?

The following steps outline how to calculate the Ionic Character Percentage using the given formula:

  1. First, determine the electronegativity of atom A (Xa).
  2. Next, determine the electronegativity of atom B (Xb).
  3. Calculate (Xa – Xb)^2.
  4. Multiply the result from step 3 by -0.25.
  5. Take the exponential of the result from step 4 using the base of the natural logarithm (e).
  6. Subtract the result from step 5 from 1.
  7. Multiply the result from step 6 by 100 to get the Ionic Character Percentage (IC%).
  8. Finally, calculate the Ionic Character Percentage (IC%).
  9. After inserting the values of Xa and Xb into the formula and performing the calculations, check your answer with the calculator above.

Example Problem:

Use the following variables as an example problem to test your knowledge:

Electronegativity of atom A (Xa) = 2.5

Electronegativity of atom B (Xb) = 1.8

Base of the natural logarithm (e) = 2.71828