Stark Effect
The shifting and splitting of atomic spectral lines caused by the presence of an external static electric field.
Governing formula
ΔE = -p · E_ext (First-order: ΔE ∝ E_ext)
SI unit
eV (Energy Shift)
In depth
The electric analogue of the Zeeman effect. The external electric field distorts atomic orbital shapes and shifts energy levels by interacting with permanent or field-induced electric dipole moments.
Examples in the real world
Measuring spectral line broadening in high-density laboratory plasmas to determine ion density and micro-electric fields.