where e = 1.602176634 × 10−19 C is the elementary charge,
Z is the charge number (dimensionless), and
E is the electric field (SI unit: V/m). The electric field can be given directly or computed from an electric potential:
where B (SI unit: T) is the magnetic flux density.
where
and
are the complex-valued fields solved for in the frequency domain,ω (SI unit: rad/s) is the angular frequency,
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(SI unit: rad) is the phase angle, and
t (SI unit: s) is time.