Diffraction of Electrons by a Crystal

atomic layers =

slits for waves of comparable wavelength

electron wave packets diffracted from atomic lattice

2 rings produced on scintillating screen

(like 2 rainbows from diffraction grating)

double the energy (E) of the electrons

by doubling the accelerating voltage

wavelength of particles halved l= h/E

ring spacing (measuring l of electron) halved


(1.) electron particles behave like waves

(2.) can measure (A) wavelength or
(B) inner atomic spacing