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<< Click to Display Table of Contents >> Navigation: Experiments > G - Electrochemical Impedance > Techniques > CombiEIS Galvanostatic > CombiEIS Galvanostatic - Experimental Sequence |
Run the CombiEIS Galvanostatic standard technique by selecting Experiment > Electrochemical Impedance > CombiEIS Galvanostatic from the Framework™ menu bar. This initiates the following sequence of events:
1.Framework™ creates a Runner window, and the CombiEIS Galvanostatic.exp script is run in this window.
2.The script creates the Setup dialog box which becomes the active window and accepts changes in the experimental parameters. This Setup window remembers the experimental settings from the last time this script was run. To restore the parameters to the values defined in the script, click the Default button.
3.The script now obtains the use of the potentiostat specified during Setup and opens the data file using the Output name. If the potentiostat is in use or the file cannot be opened, the script returns you to the Setup dialog box. The file header information is written to the data file. This information is written to the file prior to data acquisition. If the experiment is aborted, the file contains only this information. This header information includes:
•Tags identifying possible analyses.
•The current time and date.
•A list of the Setup parameters.
4.The script conditions the electrode if Conditioning was specified in the Setup. Conditioning is done by applying a fixed potential for a defined time. It establishes a known surface state on the working electrode. A plot of current versus time is displayed during the Conditioning.
5.The script then sets up data acquisition via the following steps:
a.The script determines if it is better to run a combination of the two techniques based on the frequency range, or whether the single-sine or the OptiEIS alone is the best choice. The minimum frequency must be below 0.01 Hz for OptiEIS to be included. The maximum frequency must be greater than Min Freq. × 4096 for single-sine to be included.
b.The script determines the split point as Min Freq. × 4096.
c.The OptiEIS signal is calculated and optimized as in the standard OptiEIS technique.
d.The single-sine portion of the scan is started, and individual sinusoidal responses are measured from the Max Freq. down to the split point, as calculated previously.
e.The OptiEIS portion is completed and the data is added to the plot.
6.Pressing the F2-Skip button during the single-sine portion prompts you to continue the experiment or terminate the test. Any data acquired up to that point are saved.
7.Pressing the F2-Skip button during any step quits the OptiEIS portion quits the experiment, and only the data from the single-sine portion are saved. Partial data cycles from OptiEIS are discarded because the Fourier transform leads to incorrect answers.