Studying atomic structures by aberration-corrected transmission electron microscopy

Seventy- five years after its invention, transmission electron microscopy has taken a great step forward with the introduction of aberration- corrected electron optics. An entirely new generation of instruments enables studies in condensed- matter physics and materials science to be performed at atomic- scale resolution. These new possibilities are meeting the growing demand of nanosciences and nanotechnology for the atomic- scale characterization of materials, nanosynthesized products and devices, and the validation of expected functions. Equipped with electron- energy filters and electron- energy- loss spectrometers, the new instruments allow studies not only of structure but also of elemental composition and chemical bonding. The energy resolution is about 100 milli- electron volts, and the accuracy of spatial measurements has reached a few picometers. However, understanding the results is generally not straightforward and only possible with extensive quantum- mechanical computer calculations.