Diffraction · Imaging · Spectroscopy
Electron probes: reading the evidence
From crystal diffraction to electron imaging and chemical shifts: how each instrument works, what it records and what its data can and cannot show.
The same particle, the electron, can test a wavelength, form an image or reveal an energy difference. Each instrument records a different kind of signal. Read the three articles in order, or start with the signal you want to understand.
Electron diffraction: two experiments, one wavelength test
How did electron currents scattered from nickel and rings on photographic plates turn the matter-wave idea into a quantitative test?
Ruska: making an electron image was only the beginning
What separated a magnified grid from a microscope capable of revealing finer structure?
Kai Siegbahn: when electron energies began to reveal chemistry
What turns a resolved photoelectron peak into evidence about bonding near a surface?
Three instruments, three questions
Diffraction, 1927: do the diffraction directions and the accelerating voltage match a wavelength set by momentum? Imaging, 1931–1933: can magnetic lenses in series keep finer detail of the specimen? Spectroscopy, 1950s–1960s: can resolved electron energies tell different local environments apart? The prizes came later, in 1937, 1986 and 1981.