electron vacancy

When the electron in pure silicon crosses the gap, it leaves behind an electron vacancy or "hole" in the regular silicon lattice.

K-shell) electron, causing the latter to undergo a transition to a higher-energy orbit (or wave-mechanical state) and leaving an electron vacancy (hole) in its inner shell.

Additionally, the Band-Raman calculation can now consider ("frozen orbitals") or neglect ("no hole") the effect of the electron vacancy; the frozen-orbitals approximation is considered generally superior.

The situation is complicated by the presence of holes (positively charged electron vacancies) which are generated along with the secondary electrons, and which may be expected to follow them around.

Upon one-electron oxidation of a compound with two or more equivalent ferrocene moieties the electron vacancy could be localized on one ferrocene unit or completely delocalized.

The converse is true for acceptor impurities, i.e. when all the circles are full then all the electron vacancies are filled, this is as if all the holes have ionized.

Some of the defects produce localized levels in the forbidden band, serving as charge traps; Al(III) and B(III) typically serve as hole traps while electron vacancies, titanium, germanium, and phosphorus atoms serve as electron traps.