Calculate Integrated Cottrell Equation

Calculate Integrated Cottrell Equation is used in charge-vs.-tau1/2 plots to determine the values of the parameters in the Integrated Cottrell equation for Chronocoulometry experiments. In order to use this command, you must do a linear fit on the current-vs.-tau1/2 plot.


  1. Select the Second Chart tab to show the charge-vs.-tau1/2 plot.
  2. Use the Linear Fit command to define a region of the plot.
  3. Select the Calculate Integrated Cottrell Equation command from the document menu. The Specify Linear Region to Fit window appears.
  4. Click the desired line, then the OK button.
  5. The Integrated Cottrell Equation window opens. Enter three of the four parameters of the Integrated Cottrell equation. The slope of the line, with the user-entered parameters, are used to determine the value for the one unknown using the relationship that the slope = (2nFAD1/2C)/π1/2.