Exploring the Energy Model

Once the three bands are created, a lamp with variable spectrum appears on the bottom left of the screen. The input spectrum represents the energy of light absorbed by the toothbrush.

 

Vary the input energy and determine which energies cause transitions from the valence band to conduction band.

 

Notice that after a transition occurs, the valence band turns gray and the conduction band turns black. This change illustrates that electrons now occupy the conduction band.