Ferrocene Modeling Exercise

Task 5: Generate and display the UV-Visible electronic absorption spectra of ferrocene and the mono- and diacetyl derivatives. 

Time: 10 minutes

1. Open the optimized file: File|Open "ferrocene".
2. Generate and tabulate the UV-Visible Spectrum.
   1. Select
   2. Experiment|New
   3. Select:
     
   1. Property of: Chemical Sample
   2. Property: Chemical Sample
   3. Property: UV-Visible transitions
   4. Using: ZINDO CI at current geometry
   4. Click Start.
   5. The calculation window opens.  Information about the progress of the experiment scrolls in the window.  The Tabulator may take 3 to 4 minutes, depending on your computer processor. When the calculation is done, it will say "Tabulation complete".
   6. Save the file: File|Save
3. Visualize the spectrum. 
   1. Select Analyze|UV-visible Transitions. 
   2. A screen with the visible transitions appears.
4. Select Tile from the Window menu to view the spectrum and the molecule (with the MOs involved in the transition).
5. Adjust the wavelength range.
   1. Select View|Axis Attributes from the menu bar.   
   2. Set the wavelength range for 200 to 500 nm and the intensity range from 0 to 8,000.
6. Chose the the Select Tool, , and click on a transition indicated by a triangle in the spectrum window.
   1. The transition will be highlighted in red to show that it is selected. The MO surfaces will be displayed in the other window.  
   2. The surface of the lower energy orbital is shown in green and blue. 
   3. The higher energy orbital surface is shaded in red and yellow (click in the workspace window to select both surfaces).
   4. Select the structure window. Use the rotate button,, to visualize all sides of the orbital surface.
7. Repeat the process to view the orbitals involved in the other transitions.
8. Repeat steps 2a through 2f to generate the spectra of the acetylated derivatives.
9. Compare the computed spectra with the experimental spectra for the compounds prepared.