| energy band | |
| —n | |
| physics See also energy gap a range of energies associated with the quantum states of electrons in a crystalline solid. In a semiconductor or an insulator there is a valence band containing many states, most of which are occupied. Above this is a forbidden band with only a few isolated states caused by impurities. Above this is a conduction band containing many states most of which are empty. In a metal there is a continuous valence-conduction band | |