An apparent variation of structure factors for electrons with the accelerating voltage. An observation through Kikuchi patterns

It is shown that the intensity of the Kikuchi line of the second order reflection 220 in electron diffraction patterns from a thin single-crystal of Fe-20 at.% Al alloy gradually changes with the accelerating voltage for incident electrons and vanishes at about 340 kV owing to the systematic dynamical interactions combined with the relativistic change of electron mass.