
 Quantum Physics  SolidState Device Theory 
  Electrons, therefore, do not really exist in their "orbits" as precisely defined bits of matter, or even as precisely defined waveshapes, but rather as "clouds"  the technical term is wavefunction  of probability distribution, as if each electron were "spread" or "smeared" over a range of positions and momenta. 
  An electron "shell" is a region of space around an atom's nucleus that electrons are allowed to exist in, corresponding to the stable "standing wave" patterns of de Broglie and Bohr. 
  In this notation, the shell number is shown as an integer, the subshell as a letter (s,p,d,f), and the total number of electrons in the subshell (all orbitals, all spins) as a superscript. 
 www.opampelectronics.com /tutorials/quantum_physics_3_02_02.htm (4716 words) 
