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Department of Chemistry

University of Pittsburgh at Johnstown

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Ferrocene

Electrostatic Interactions -- Atom Partial Charges

Task: Generate and view the atom partial charges in of nitrocyclopentadiene ().

Time: 3 minutes

  1. Open the file:  File|Open "nitrocyclo-PM5".
  2. Select Experiment|New  
  3. Select:
    1. Property of: atom
    2. Property: partial charge
    3. Using: PM5 geometry with PM5 wavefunction
    4. Click Start.
  4. Save the file File|Save "nitrocyclo-PM5"
  5. Visualize the bond order and partial charges:
    1. Select View|Partial Chg & Calc. Bond Order
    2. Partial charges appear as colored spheres. Yellow is negative, red is positive and the diameter is proportional to the charge.
    3. The thickness of the bond is proportional to the calculated bond order. The double bonds of the cyclopentadiene ring are twice as thick as the single bonds.
  6. To return to the original rendering:
    1. Select View|Color by Element.
    2. Select View|Ball & Cylinder.

In the next lesson you will generate and visualize the electron density isosurface of nitrocyclopentadiene.