An Electrostatic Multipole

An electrostatic multipole is defined by the command: 9 E(LECTROSTATIC) M(ULTIPOLE) <effective length $\ell$ of multipole in meter> <V_Q in kV at electrode> <V_H in kV at electrode> <V_O in kV at electrode> <V_D in kV at electrode> <V_Z in kV at electrode> <aperture radius G₀ in meter> ; [example: E   M   0.1   1.0   0   0   0   0   0.03 ;]

V_Q, V_H, V_O, V_D and V_Z here are the quadrupole-, hexapole-, octopole-, decapole- and dodecapole-components of the electrode potential. For positive or negative values of V_Q, V_H, V_O, V_D, V_Z particles with positive x-values are driven towards or away from the optic axis, respectively.

Analogously to the magnetic case the multipole-command is also applicable for a pure quadrupole, hexapole, octopole, decapole or dodecapole. However, to save computer time it is advisable to use in such cases the following commands: