Experimenting with different charge configurations

Now that you know how to change the charges in a simulation, here are a few numerical experiments that you could do:

• Try placing a single large negative charge (i.e., -4e) at the center of the nanotube. Observe the simulation for about 10 ps. What happens to the water file inside the nanotube? Can you explain what causes this behavior?

• What happens if you place instead a positive charge at the center?

• You may experiment with a few charge distributions of your choosing. For example, what happens if you reverse the charges that you have applied in the previous section? What happens if all your charges are vertically aligned along the nanotube, is it the same as if they were distributed somewhere else around the tube? And finally, would the answer to this last question remain the same if you inverted all the charges in the tube?