Band Simulator
This simulator presents molecular orbitals (top window), two kinds of energy level diagram (lower left and right windows), and the band structure (right-hand side of the right window) for a linear array of hydrogen atom 1s atomic orbitals. Actually, any linear group of s orbitals would behave similarly.
Controls
Internuclear Separation Slider
Adjust this to set the separation between adjacent nuclei in picometres. The adjustment occurs after the mouse button is released. Note that the spacing of the nuclei in the top window is the same, and too many nuclei, too far apart will overflow out of it to the right. Also the top window will not display molecular orbitals for more than 10 nuclei. Messages will appear for either of these conditions.
Number of Atoms Dropdown
Use this to select how many nuclei to show.
Occupancy Dropdown
Choose empty, half-filled or filled. In the right hand energy level and band diagram, the filled levels are shown blue, and the empty ones green.
Molecular Orbital Display
Click on any energy level in the left-hand side of the right hand diagram to display the corresponding molecular orbital. You need to be accurate with the cursor, that is, within + or - one pixel in the vertical direction.
Density of States
Note that this window will only show something resembling a band if the energy levels are very close together, so chose lots of nuclei with a long internuclear distance to see the band effect.