I was wondering, how close does the energy level have to match for the electron to accept it – does it have to be completely precise? And does the electron ever make a mistake so that it somehow only goes up to half an energy level between the orbitals? In general, the larger the atom, the more complex the configuration of electrons you’ll find, and the more spectral lines it’ll have. With so many energy levels available, packed so close together, it’s necessary to start talking about “energy bands”. Electrons never transition half-way to other energy levels, but they can exist in a “super-position” of multiple energy levels, which is kinda the next best thing.