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Dushinsky Transformation Window

This window displays the normal mode displacements (K) between two electronic states, and the Dushinsky transformation matrix (J) between them. If the information is available, then the geometries and normal modes for the two states are also displayed. To bring up the window right click on the transition moment between the two states and select "Dushinsky Matrix...".

The lower panel, visible if nNuclei for the molecule is > 0, shows the atom positions and normal modes for each state. The atoms for the state shown in the bra (here Ion) are plotted with open circles for the atoms and the atoms for the state in the ket are shown as filled circles. To plot a particular normal mode, click on the appropriate column, or click on the "Displacement" column to just show the atom positions. In these plots the matching atoms or atom motions are joined by dotted lines - this allows for a check that the same choice of axes and atom and mode numbering has been made for the two states. (This can also show as large off-diagonal elements for the Dushinsky matrix, or negative values on the diagonal.) If the states have been set up inconsistently, then the intensity calculations may not be correct. For example if the two Cl atoms in the above example were swapped between the two states then the atom position plot will look like:

CCl2 with Cl atoms switched

This particular problem could be solved by right clicking on the appropriate atom and using the "Move Up" command. Other possibilities include changing the order or sign of the modes.

Split Drag to resize the upper and lower parts.
Displacements along the normal co-ordinates, J. If "Calculate" is not selected, these can be edited in this window.
Dushinsky transformation matrix (J) between normal coordinates.
PlotPlaneGroup Select plane to plot
MagnificationLabelMagnificationSpin Scale factor for normal mode zero point displacements
Select arrows plotted - see The l Matrix Window for details.
ShowTRCheckBox Show Translational and Rotational normal mode transformations.
CalculateCheckBox Select for normal mode displacements and the Dushinsky matrix to be calculated from the l matrices and equilibrium geometry for the two electronic states. If not set, the values are taken from the modes under the Multidimensional Franck Condon Factor object.
Rotates the plotted image by the given angle about the horizontal axis.