Pre-exponential Factor Calculator

Calculate the Arrhenius pre-exponential factor (A)

About Pre-exponential Factor

The pre-exponential factor (A), also called the frequency factor, represents the frequency of molecular collisions with correct orientation for reaction.

Typical values:

  • Unimolecular reactions: 10¹² - 10¹⁴ s⁻¹
  • Bimolecular reactions: 10¹⁰ - 10¹¹ M⁻¹s⁻¹

A includes both the collision frequency (Z) and steric factor (p): A = p × Z