DigiElch8 Help

•Command: Edit        
Edit the parameters associated with the active experiment.

•Command: Run          
Runs a CA experiment for the specified scan and experimental parameters.

•Command: Measure IR-Drop & Run
Determines the uncompensated ohmic resistance, Ru (Ohm), and runs a CA experiment setting the IR-compensation to the highest possible value ≤ Ru (Ohm).

•Command: Run Accumulations
Accumulates a series of CA experiments for the specified scan and experimental parameters. Should be used only when conducting experiments on an automatic mercury electrode where a fresh drop is generated each time before  starting a new accumulation.  The number of accumulations can be specified in the associated Properties Window.
 

•Command: IR-Drop  
Performs an AC (impedance) experiment from which the uncompensated ohmic resistance, Ru (Ohm), and the double layer capacity, Cdl (F), of the electrode is determined.
 

•Command: Experimental Background Correction        
After replacing the sample with a solution containing only the solvent and the supporting electrolyte this command can be used to measure the background current using exactly the same scan and experimental parameters as in the active experiment. The measured background current is then subtracted from the CA experiment.
 

•Command: Simulated Background Correction
Subtracts a simulated background curve from the experimental one. The simulated background curve is considered a capacity current the potential dependence of which is given by a polynomial of order up to four. The coefficients involved in the polynomial can be defined in a dialog box that appears when clicking this command

In the simplest case the background current is simulated using the constant Ru (Ohm) and Cdl (F) value determined experimentally.
 

•Command: Smooth Curve
Smooth the experimental current curve by means of a Digital Smoothing Filter on the basis of a Savitzky-Golay Filter. The filter coefficients of the latter can be defined in the associated Properties Window.

•Command: Circles                
The active current curve is plotted in the form of open circles.  

•Command: Filled Circles
The active current curve is plotted in the form of filled circles.

•Command: Min/Max Info
Shows the E-I-couple referring to the minimum/maximum found in a mouse drawn rectangle.  

•Command: Plot Graph
Display data obtained by selecting a  a particular current point by double clicking on the active current curve)  as function of scan rate, electrode size, species concentration etc. The graph is displayed in the Tab-Window: Plot Graph.

•Command: Compute
Opens a dialog box that enables the user to compute data from Screen Info.

•Command: Next Scan Segment
Activates the next scan segment If the active simulation consists of more than one.
 

•Command: Exclude                
Use the mouse to draw a rectangle around the current points which are to be excluded from data fitting. The command can be repeatedly applied. After releasing the mouse button all current point excluded from data fitting are plotted in red. For this reason red should not be selected as color for the active or inactive experiment.
 

•Command: Unmark Active Curve
Undoes the Exclude-command for the active experiment.

•Command: Unmark All Curves
Undoes the Exclude-command for all experiments shown in the Tab-Window: Experiments.

•Command: Remove Ringing
This command is not supported for CA-experiments. It remains always disabled.

•Clipboard Command: Copy        
Copy the active experiment and put the copy on the clipboard.

•Clipboard Command: Cut
Cut the active experiment and put it on the clipboard.

•Clipboard Command: Paste
Paste clipboard content into the Tab-Window: Experiments.
 

•RAM_Disk Command: RAM-Disk
Opens a dialog box showing the actual content of the RAM-Disk. The RAM-Disk stores data in use-file format. It can be used for importing experiments from the RAM-Disk into the Tab-Window: Experiments where they can be used as target curves in a Data Fitting Project.  Note that the Tab-Window: Experiments  enables the user to modify the experimental parameters before subjecting them to Data Fitting. The latter allows, for instance, the dilution of the experimental current curve which can lead to a considerable saving of computation time.  It cannot be accomplished when doing the Data Fitting using directly the experiments measured in the Tab-Window: GAMRY-Experiments.
 

•RAM-Disk Command: Export              
Exports the active experiment in use-format and stores the use-file in the RAM-Disk.
 

•RAM-Disk Command: Export all Experiments to RAM-Disk        
Exports all experiments shown in the Experiments-window in use-format and stores the use-files in the RAM-Disk.
 

•File Command: Export        
Exports the active experiment as use- or txt- file analogously to exporting a simulation.

•File Command: Export all Experiments
Exports all experiments  as use- or txt-files analogously to exporting all simulations.

•Command: Next        
The current curve referring to the next experiment is activated.  
 

•Command: Previous
The current curve referring to the previous experiment is activated.  
 

•Command: Delete Active Experiment        
Deletes the active experiment.  

•Command: Delete All Experiments
Deletes all experiments shown in the Tab-Window: Experiments.

•Command: Zoom                
Zooms the screen display by pressing down the left mouse button and draw a rectangle around the region which is to be zoomed. The zoom command can be repeatedly applied.

•Command: Unzoom
Undo the zoom command.

•Command: Refresh Screen
Removes Min/Max-Info and redraws the screen display.

•Option: Plot

oCurrent
Plots current vs. potential

oSemi-Integral
Plots the semi-integrated current curve as function of the potential

oSemi-Differential
Plots the semi-differentiated current curve as function of the potential

oDiff-Integral
Plots the Diff-Integral of the current curve as function of the potential. The order of the Diff-Integral can be specified in a dialog box that shows up after selecting this option. (see: "The Fractional Calculus: Theory and Applications of Differentiation and Integration to Arbitrary Order" by Keith B. Oldham and Jerome Spanier (Dover Books on Mathematics).
 

•Command: Add/Subtract        
Opens a dialog box that can be used for selecting two of the current curves shown on the Tab-Window: Experiments. Then a new experiment is created. The current curve of the latter is the sum or difference of the two selected curves.

•Command: Connect    
If  a GAMRY potentiostat is plugged in the USB port of a computer running DigiElch this command connects the potentiostat with DigiElch.