Monochromated, aberration-corrected scanning transmission electron microscopes (MAC-STEMs) are able to form intense electron probes as small as 0.5-1 Å in diameter, analyze single atoms spectroscopically (by electron energy loss spectroscopy (EELS) or energy-dispersive X-ray spectroscopy (EDXS)), detect vibrational EEL spectra, and perform many other types of experiments that we did not think would become possible as recently as 5 years ago.
